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
  29 #include <net/sock.h>
  30 #include <net/tcp.h>
  31 #include <net/smc.h>
  32 #include <asm/ioctls.h>
  33
  34 #include <net/net_namespace.h>
  35 #include <net/netns/generic.h>
  36 #include "smc_netns.h"
  37
  38 #include "smc.h"
  39 #include "smc_clc.h"
  40 #include "smc_llc.h"
  41 #include "smc_cdc.h"
  42 #include "smc_core.h"
  43 #include "smc_ib.h"
  44 #include "smc_ism.h"
  45 #include "smc_pnet.h"
  46 #include "smc_tx.h"
  47 #include "smc_rx.h"
  48 #include "smc_close.h"
  49
  50 static DEFINE_MUTEX(smc_server_lgr_pending);    /* serialize link group
  51                                                  * creation on server
  52                                                  */
  53 static DEFINE_MUTEX(smc_client_lgr_pending);    /* serialize link group
  54                                                  * creation on client
  55                                                  */
  56
  57 static void smc_tcp_listen_work(struct work_struct *);
  58 static void smc_connect_work(struct work_struct *);
  59
  60 static void smc_set_keepalive(struct sock *sk, int val)
  61 {
  62         struct smc_sock *smc = smc_sk(sk);
  63
  64         smc->clcsock->sk->sk_prot->keepalive(smc->clcsock->sk, val);
  65 }
  66
  67 static struct smc_hashinfo smc_v4_hashinfo = {
  68         .lock = __RW_LOCK_UNLOCKED(smc_v4_hashinfo.lock),
  69 };
  70
  71 static struct smc_hashinfo smc_v6_hashinfo = {
  72         .lock = __RW_LOCK_UNLOCKED(smc_v6_hashinfo.lock),
  73 };
  74
  75 int smc_hash_sk(struct sock *sk)
  76 {
  77         struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
  78         struct hlist_head *head;
  79
  80         head = &h->ht;
  81
  82         write_lock_bh(&h->lock);
  83         sk_add_node(sk, head);
  84         sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
  85         write_unlock_bh(&h->lock);
  86
  87         return 0;
  88 }
  89 EXPORT_SYMBOL_GPL(smc_hash_sk);
  90
  91 void smc_unhash_sk(struct sock *sk)
  92 {
  93         struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
  94
  95         write_lock_bh(&h->lock);
  96         if (sk_del_node_init(sk))
  97                 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
  98         write_unlock_bh(&h->lock);
  99 }
 100 EXPORT_SYMBOL_GPL(smc_unhash_sk);
 101
 102 struct proto smc_proto = {
 103         .name           = "SMC",
 104         .owner          = THIS_MODULE,
 105         .keepalive      = smc_set_keepalive,
 106         .hash           = smc_hash_sk,
 107         .unhash         = smc_unhash_sk,
 108         .obj_size       = sizeof(struct smc_sock),
 109         .h.smc_hash     = &smc_v4_hashinfo,
 110         .slab_flags     = SLAB_TYPESAFE_BY_RCU,
 111 };
 112 EXPORT_SYMBOL_GPL(smc_proto);
 113
 114 struct proto smc_proto6 = {
 115         .name           = "SMC6",
 116         .owner          = THIS_MODULE,
 117         .keepalive      = smc_set_keepalive,
 118         .hash           = smc_hash_sk,
 119         .unhash         = smc_unhash_sk,
 120         .obj_size       = sizeof(struct smc_sock),
 121         .h.smc_hash     = &smc_v6_hashinfo,
 122         .slab_flags     = SLAB_TYPESAFE_BY_RCU,
 123 };
 124 EXPORT_SYMBOL_GPL(smc_proto6);
 125
 126 static void smc_restore_fallback_changes(struct smc_sock *smc)
 127 {
 128         smc->clcsock->file->private_data = smc->sk.sk_socket;
 129         smc->clcsock->file = NULL;
 130 }
 131
 132 static int __smc_release(struct smc_sock *smc)
 133 {
 134         struct sock *sk = &smc->sk;
 135         int rc = 0;
 136
 137         if (!smc->use_fallback) {
 138                 rc = smc_close_active(smc);
 139                 sock_set_flag(sk, SOCK_DEAD);
 140                 sk->sk_shutdown |= SHUTDOWN_MASK;
 141         } else {
 142                 if (sk->sk_state != SMC_LISTEN && sk->sk_state != SMC_INIT)
 143                         sock_put(sk); /* passive closing */
 144                 if (sk->sk_state == SMC_LISTEN) {
 145                         /* wake up clcsock accept */
 146                         rc = kernel_sock_shutdown(smc->clcsock, SHUT_RDWR);
 147                 }
 148                 sk->sk_state = SMC_CLOSED;
 149                 sk->sk_state_change(sk);
 150                 smc_restore_fallback_changes(smc);
 151         }
 152
 153         sk->sk_prot->unhash(sk);
 154
 155         if (sk->sk_state == SMC_CLOSED) {
 156                 if (smc->clcsock) {
 157                         release_sock(sk);
 158                         smc_clcsock_release(smc);
 159                         lock_sock(sk);
 160                 }
 161                 if (!smc->use_fallback)
 162                         smc_conn_free(&smc->conn);
 163         }
 164
 165         return rc;
 166 }
 167
 168 static int smc_release(struct socket *sock)
 169 {
 170         struct sock *sk = sock->sk;
 171         struct smc_sock *smc;
 172         int rc = 0;
 173
 174         if (!sk)
 175                 goto out;
 176
 177         smc = smc_sk(sk);
 178
 179         /* cleanup for a dangling non-blocking connect */
 180         if (smc->connect_nonblock && sk->sk_state == SMC_INIT)
 181                 tcp_abort(smc->clcsock->sk, ECONNABORTED);
 182         flush_work(&smc->connect_work);
 183
 184         if (sk->sk_state == SMC_LISTEN)
 185                 /* smc_close_non_accepted() is called and acquires
 186                  * sock lock for child sockets again
 187                  */
 188                 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 189         else
 190                 lock_sock(sk);
 191
 192         rc = __smc_release(smc);
 193
 194         /* detach socket */
 195         sock_orphan(sk);
 196         sock->sk = NULL;
 197         release_sock(sk);
 198
 199         sock_put(sk); /* final sock_put */
 200 out:
 201         return rc;
 202 }
 203
 204 static void smc_destruct(struct sock *sk)
 205 {
 206         if (sk->sk_state != SMC_CLOSED)
 207                 return;
 208         if (!sock_flag(sk, SOCK_DEAD))
 209                 return;
 210
 211         sk_refcnt_debug_dec(sk);
 212 }
 213
 214 static struct sock *smc_sock_alloc(struct net *net, struct socket *sock,
 215                                    int protocol)
 216 {
 217         struct smc_sock *smc;
 218         struct proto *prot;
 219         struct sock *sk;
 220
 221         prot = (protocol == SMCPROTO_SMC6) ? &smc_proto6 : &smc_proto;
 222         sk = sk_alloc(net, PF_SMC, GFP_KERNEL, prot, 0);
 223         if (!sk)
 224                 return NULL;
 225
 226         sock_init_data(sock, sk); /* sets sk_refcnt to 1 */
 227         sk->sk_state = SMC_INIT;
 228         sk->sk_destruct = smc_destruct;
 229         sk->sk_protocol = protocol;
 230         smc = smc_sk(sk);
 231         INIT_WORK(&smc->tcp_listen_work, smc_tcp_listen_work);
 232         INIT_WORK(&smc->connect_work, smc_connect_work);
 233         INIT_DELAYED_WORK(&smc->conn.tx_work, smc_tx_work);
 234         INIT_LIST_HEAD(&smc->accept_q);
 235         spin_lock_init(&smc->accept_q_lock);
 236         spin_lock_init(&smc->conn.send_lock);
 237         sk->sk_prot->hash(sk);
 238         sk_refcnt_debug_inc(sk);
 239         mutex_init(&smc->clcsock_release_lock);
 240
 241         return sk;
 242 }
 243
 244 static int smc_bind(struct socket *sock, struct sockaddr *uaddr,
 245                     int addr_len)
 246 {
 247         struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
 248         struct sock *sk = sock->sk;
 249         struct smc_sock *smc;
 250         int rc;
 251
 252         smc = smc_sk(sk);
 253
 254         /* replicate tests from inet_bind(), to be safe wrt. future changes */
 255         rc = -EINVAL;
 256         if (addr_len < sizeof(struct sockaddr_in))
 257                 goto out;
 258
 259         rc = -EAFNOSUPPORT;
 260         if (addr->sin_family != AF_INET &&
 261             addr->sin_family != AF_INET6 &&
 262             addr->sin_family != AF_UNSPEC)
 263                 goto out;
 264         /* accept AF_UNSPEC (mapped to AF_INET) only if s_addr is INADDR_ANY */
 265         if (addr->sin_family == AF_UNSPEC &&
 266             addr->sin_addr.s_addr != htonl(INADDR_ANY))
 267                 goto out;
 268
 269         lock_sock(sk);
 270
 271         /* Check if socket is already active */
 272         rc = -EINVAL;
 273         if (sk->sk_state != SMC_INIT || smc->connect_nonblock)
 274                 goto out_rel;
 275
 276         smc->clcsock->sk->sk_reuse = sk->sk_reuse;
 277         rc = kernel_bind(smc->clcsock, uaddr, addr_len);
 278
 279 out_rel:
 280         release_sock(sk);
 281 out:
 282         return rc;
 283 }
 284
 285 static void smc_copy_sock_settings(struct sock *nsk, struct sock *osk,
 286                                    unsigned long mask)
 287 {
 288         /* options we don't get control via setsockopt for */
 289         nsk->sk_type = osk->sk_type;
 290         nsk->sk_sndbuf = osk->sk_sndbuf;
 291         nsk->sk_rcvbuf = osk->sk_rcvbuf;
 292         nsk->sk_sndtimeo = osk->sk_sndtimeo;
 293         nsk->sk_rcvtimeo = osk->sk_rcvtimeo;
 294         nsk->sk_mark = osk->sk_mark;
 295         nsk->sk_priority = osk->sk_priority;
 296         nsk->sk_rcvlowat = osk->sk_rcvlowat;
 297         nsk->sk_bound_dev_if = osk->sk_bound_dev_if;
 298         nsk->sk_err = osk->sk_err;
 299
 300         nsk->sk_flags &= ~mask;
 301         nsk->sk_flags |= osk->sk_flags & mask;
 302 }
 303
 304 #define SK_FLAGS_SMC_TO_CLC ((1UL << SOCK_URGINLINE) | \
 305                              (1UL << SOCK_KEEPOPEN) | \
 306                              (1UL << SOCK_LINGER) | \
 307                              (1UL << SOCK_BROADCAST) | \
 308                              (1UL << SOCK_TIMESTAMP) | \
 309                              (1UL << SOCK_DBG) | \
 310                              (1UL << SOCK_RCVTSTAMP) | \
 311                              (1UL << SOCK_RCVTSTAMPNS) | \
 312                              (1UL << SOCK_LOCALROUTE) | \
 313                              (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
 314                              (1UL << SOCK_RXQ_OVFL) | \
 315                              (1UL << SOCK_WIFI_STATUS) | \
 316                              (1UL << SOCK_NOFCS) | \
 317                              (1UL << SOCK_FILTER_LOCKED) | \
 318                              (1UL << SOCK_TSTAMP_NEW))
 319 /* copy only relevant settings and flags of SOL_SOCKET level from smc to
 320  * clc socket (since smc is not called for these options from net/core)
 321  */
 322 static void smc_copy_sock_settings_to_clc(struct smc_sock *smc)
 323 {
 324         smc_copy_sock_settings(smc->clcsock->sk, &smc->sk, SK_FLAGS_SMC_TO_CLC);
 325 }
 326
 327 #define SK_FLAGS_CLC_TO_SMC ((1UL << SOCK_URGINLINE) | \
 328                              (1UL << SOCK_KEEPOPEN) | \
 329                              (1UL << SOCK_LINGER) | \
 330                              (1UL << SOCK_DBG))
 331 /* copy only settings and flags relevant for smc from clc to smc socket */
 332 static void smc_copy_sock_settings_to_smc(struct smc_sock *smc)
 333 {
 334         smc_copy_sock_settings(&smc->sk, smc->clcsock->sk, SK_FLAGS_CLC_TO_SMC);
 335 }
 336
 337 /* register a new rmb, send confirm_rkey msg to register with peer */
 338 static int smc_reg_rmb(struct smc_link *link, struct smc_buf_desc *rmb_desc,
 339                        bool conf_rkey)
 340 {
 341         if (!rmb_desc->wr_reg) {
 342                 /* register memory region for new rmb */
 343                 if (smc_wr_reg_send(link, rmb_desc->mr_rx[SMC_SINGLE_LINK])) {
 344                         rmb_desc->regerr = 1;
 345                         return -EFAULT;
 346                 }
 347                 rmb_desc->wr_reg = 1;
 348         }
 349         if (!conf_rkey)
 350                 return 0;
 351         /* exchange confirm_rkey msg with peer */
 352         if (smc_llc_do_confirm_rkey(link, rmb_desc)) {
 353                 rmb_desc->regerr = 1;
 354                 return -EFAULT;
 355         }
 356         return 0;
 357 }
 358
 359 static int smc_clnt_conf_first_link(struct smc_sock *smc)
 360 {
 361         struct net *net = sock_net(smc->clcsock->sk);
 362         struct smc_link_group *lgr = smc->conn.lgr;
 363         struct smc_link *link;
 364         int rest;
 365         int rc;
 366
 367         link = &lgr->lnk[SMC_SINGLE_LINK];
 368         /* receive CONFIRM LINK request from server over RoCE fabric */
 369         rest = wait_for_completion_interruptible_timeout(
 370                 &link->llc_confirm,
 371                 SMC_LLC_WAIT_FIRST_TIME);
 372         if (rest <= 0) {
 373                 struct smc_clc_msg_decline dclc;
 374
 375                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
 376                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
 377                 return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
 378         }
 379
 380         if (link->llc_confirm_rc)
 381                 return SMC_CLC_DECL_RMBE_EC;
 382
 383         rc = smc_ib_modify_qp_rts(link);
 384         if (rc)
 385                 return SMC_CLC_DECL_ERR_RDYLNK;
 386
 387         smc_wr_remember_qp_attr(link);
 388
 389         if (smc_reg_rmb(link, smc->conn.rmb_desc, false))
 390                 return SMC_CLC_DECL_ERR_REGRMB;
 391
 392         /* send CONFIRM LINK response over RoCE fabric */
 393         rc = smc_llc_send_confirm_link(link, SMC_LLC_RESP);
 394         if (rc < 0)
 395                 return SMC_CLC_DECL_TIMEOUT_CL;
 396
 397         /* receive ADD LINK request from server over RoCE fabric */
 398         rest = wait_for_completion_interruptible_timeout(&link->llc_add,
 399                                                          SMC_LLC_WAIT_TIME);
 400         if (rest <= 0) {
 401                 struct smc_clc_msg_decline dclc;
 402
 403                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
 404                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
 405                 return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_AL : rc;
 406         }
 407
 408         /* send add link reject message, only one link supported for now */
 409         rc = smc_llc_send_add_link(link,
 410                                    link->smcibdev->mac[link->ibport - 1],
 411                                    link->gid, SMC_LLC_RESP);
 412         if (rc < 0)
 413                 return SMC_CLC_DECL_TIMEOUT_AL;
 414
 415         smc_llc_link_active(link, net->ipv4.sysctl_tcp_keepalive_time);
 416
 417         return 0;
 418 }
 419
 420 static void smcr_conn_save_peer_info(struct smc_sock *smc,
 421                                      struct smc_clc_msg_accept_confirm *clc)
 422 {
 423         int bufsize = smc_uncompress_bufsize(clc->rmbe_size);
 424
 425         smc->conn.peer_rmbe_idx = clc->rmbe_idx;
 426         smc->conn.local_tx_ctrl.token = ntohl(clc->rmbe_alert_token);
 427         smc->conn.peer_rmbe_size = bufsize;
 428         atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
 429         smc->conn.tx_off = bufsize * (smc->conn.peer_rmbe_idx - 1);
 430 }
 431
 432 static void smcd_conn_save_peer_info(struct smc_sock *smc,
 433                                      struct smc_clc_msg_accept_confirm *clc)
 434 {
 435         int bufsize = smc_uncompress_bufsize(clc->dmbe_size);
 436
 437         smc->conn.peer_rmbe_idx = clc->dmbe_idx;
 438         smc->conn.peer_token = clc->token;
 439         /* msg header takes up space in the buffer */
 440         smc->conn.peer_rmbe_size = bufsize - sizeof(struct smcd_cdc_msg);
 441         atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
 442         smc->conn.tx_off = bufsize * smc->conn.peer_rmbe_idx;
 443 }
 444
 445 static void smc_conn_save_peer_info(struct smc_sock *smc,
 446                                     struct smc_clc_msg_accept_confirm *clc)
 447 {
 448         if (smc->conn.lgr->is_smcd)
 449                 smcd_conn_save_peer_info(smc, clc);
 450         else
 451                 smcr_conn_save_peer_info(smc, clc);
 452 }
 453
 454 static void smc_link_save_peer_info(struct smc_link *link,
 455                                     struct smc_clc_msg_accept_confirm *clc)
 456 {
 457         link->peer_qpn = ntoh24(clc->qpn);
 458         memcpy(link->peer_gid, clc->lcl.gid, SMC_GID_SIZE);
 459         memcpy(link->peer_mac, clc->lcl.mac, sizeof(link->peer_mac));
 460         link->peer_psn = ntoh24(clc->psn);
 461         link->peer_mtu = clc->qp_mtu;
 462 }
 463
 464 static void smc_switch_to_fallback(struct smc_sock *smc)
 465 {
 466         smc->use_fallback = true;
 467         if (smc->sk.sk_socket && smc->sk.sk_socket->file) {
 468                 smc->clcsock->file = smc->sk.sk_socket->file;
 469                 smc->clcsock->file->private_data = smc->clcsock;
 470         }
 471 }
 472
 473 /* fall back during connect */
 474 static int smc_connect_fallback(struct smc_sock *smc, int reason_code)
 475 {
 476         smc_switch_to_fallback(smc);
 477         smc->fallback_rsn = reason_code;
 478         smc_copy_sock_settings_to_clc(smc);
 479         smc->connect_nonblock = 0;
 480         if (smc->sk.sk_state == SMC_INIT)
 481                 smc->sk.sk_state = SMC_ACTIVE;
 482         return 0;
 483 }
 484
 485 /* decline and fall back during connect */
 486 static int smc_connect_decline_fallback(struct smc_sock *smc, int reason_code)
 487 {
 488         int rc;
 489
 490         if (reason_code < 0) { /* error, fallback is not possible */
 491                 if (smc->sk.sk_state == SMC_INIT)
 492                         sock_put(&smc->sk); /* passive closing */
 493                 return reason_code;
 494         }
 495         if (reason_code != SMC_CLC_DECL_PEERDECL) {
 496                 rc = smc_clc_send_decline(smc, reason_code);
 497                 if (rc < 0) {
 498                         if (smc->sk.sk_state == SMC_INIT)
 499                                 sock_put(&smc->sk); /* passive closing */
 500                         return rc;
 501                 }
 502         }
 503         return smc_connect_fallback(smc, reason_code);
 504 }
 505
 506 /* abort connecting */
 507 static int smc_connect_abort(struct smc_sock *smc, int reason_code,
 508                              int local_contact)
 509 {
 510         if (local_contact == SMC_FIRST_CONTACT)
 511                 smc_lgr_forget(smc->conn.lgr);
 512         if (smc->conn.lgr->is_smcd)
 513                 /* there is only one lgr role for SMC-D; use server lock */
 514                 mutex_unlock(&smc_server_lgr_pending);
 515         else
 516                 mutex_unlock(&smc_client_lgr_pending);
 517
 518         smc_conn_free(&smc->conn);
 519         smc->connect_nonblock = 0;
 520         return reason_code;
 521 }
 522
 523 /* check if there is a rdma device available for this connection. */
 524 /* called for connect and listen */
 525 static int smc_find_rdma_device(struct smc_sock *smc, struct smc_init_info *ini)
 526 {
 527         /* PNET table look up: search active ib_device and port
 528          * within same PNETID that also contains the ethernet device
 529          * used for the internal TCP socket
 530          */
 531         smc_pnet_find_roce_resource(smc->clcsock->sk, ini);
 532         if (!ini->ib_dev)
 533                 return SMC_CLC_DECL_NOSMCRDEV;
 534         return 0;
 535 }
 536
 537 /* check if there is an ISM device available for this connection. */
 538 /* called for connect and listen */
 539 static int smc_find_ism_device(struct smc_sock *smc, struct smc_init_info *ini)
 540 {
 541         /* Find ISM device with same PNETID as connecting interface  */
 542         smc_pnet_find_ism_resource(smc->clcsock->sk, ini);
 543         if (!ini->ism_dev)
 544                 return SMC_CLC_DECL_NOSMCDDEV;
 545         return 0;
 546 }
 547
 548 /* Check for VLAN ID and register it on ISM device just for CLC handshake */
 549 static int smc_connect_ism_vlan_setup(struct smc_sock *smc,
 550                                       struct smc_init_info *ini)
 551 {
 552         if (ini->vlan_id && smc_ism_get_vlan(ini->ism_dev, ini->vlan_id))
 553                 return SMC_CLC_DECL_ISMVLANERR;
 554         return 0;
 555 }
 556
 557 /* cleanup temporary VLAN ID registration used for CLC handshake. If ISM is
 558  * used, the VLAN ID will be registered again during the connection setup.
 559  */
 560 static int smc_connect_ism_vlan_cleanup(struct smc_sock *smc, bool is_smcd,
 561                                         struct smc_init_info *ini)
 562 {
 563         if (!is_smcd)
 564                 return 0;
 565         if (ini->vlan_id && smc_ism_put_vlan(ini->ism_dev, ini->vlan_id))
 566                 return SMC_CLC_DECL_CNFERR;
 567         return 0;
 568 }
 569
 570 /* CLC handshake during connect */
 571 static int smc_connect_clc(struct smc_sock *smc, int smc_type,
 572                            struct smc_clc_msg_accept_confirm *aclc,
 573                            struct smc_init_info *ini)
 574 {
 575         int rc = 0;
 576
 577         /* do inband token exchange */
 578         rc = smc_clc_send_proposal(smc, smc_type, ini);
 579         if (rc)
 580                 return rc;
 581         /* receive SMC Accept CLC message */
 582         return smc_clc_wait_msg(smc, aclc, sizeof(*aclc), SMC_CLC_ACCEPT,
 583                                 CLC_WAIT_TIME);
 584 }
 585
 586 /* setup for RDMA connection of client */
 587 static int smc_connect_rdma(struct smc_sock *smc,
 588                             struct smc_clc_msg_accept_confirm *aclc,
 589                             struct smc_init_info *ini)
 590 {
 591         struct smc_link *link;
 592         int reason_code = 0;
 593
 594         ini->is_smcd = false;
 595         ini->ib_lcl = &aclc->lcl;
 596         ini->ib_clcqpn = ntoh24(aclc->qpn);
 597         ini->srv_first_contact = aclc->hdr.flag;
 598
 599         mutex_lock(&smc_client_lgr_pending);
 600         reason_code = smc_conn_create(smc, ini);
 601         if (reason_code) {
 602                 mutex_unlock(&smc_client_lgr_pending);
 603                 return reason_code;
 604         }
 605         link = &smc->conn.lgr->lnk[SMC_SINGLE_LINK];
 606
 607         smc_conn_save_peer_info(smc, aclc);
 608
 609         /* create send buffer and rmb */
 610         if (smc_buf_create(smc, false))
 611                 return smc_connect_abort(smc, SMC_CLC_DECL_MEM,
 612                                          ini->cln_first_contact);
 613
 614         if (ini->cln_first_contact == SMC_FIRST_CONTACT)
 615                 smc_link_save_peer_info(link, aclc);
 616
 617         if (smc_rmb_rtoken_handling(&smc->conn, aclc))
 618                 return smc_connect_abort(smc, SMC_CLC_DECL_ERR_RTOK,
 619                                          ini->cln_first_contact);
 620
 621         smc_close_init(smc);
 622         smc_rx_init(smc);
 623
 624         if (ini->cln_first_contact == SMC_FIRST_CONTACT) {
 625                 if (smc_ib_ready_link(link))
 626                         return smc_connect_abort(smc, SMC_CLC_DECL_ERR_RDYLNK,
 627                                                  ini->cln_first_contact);
 628         } else {
 629                 if (smc_reg_rmb(link, smc->conn.rmb_desc, true))
 630                         return smc_connect_abort(smc, SMC_CLC_DECL_ERR_REGRMB,
 631                                                  ini->cln_first_contact);
 632         }
 633         smc_rmb_sync_sg_for_device(&smc->conn);
 634
 635         reason_code = smc_clc_send_confirm(smc);
 636         if (reason_code)
 637                 return smc_connect_abort(smc, reason_code,
 638                                          ini->cln_first_contact);
 639
 640         smc_tx_init(smc);
 641
 642         if (ini->cln_first_contact == SMC_FIRST_CONTACT) {
 643                 /* QP confirmation over RoCE fabric */
 644                 reason_code = smc_clnt_conf_first_link(smc);
 645                 if (reason_code)
 646                         return smc_connect_abort(smc, reason_code,
 647                                                  ini->cln_first_contact);
 648         }
 649         mutex_unlock(&smc_client_lgr_pending);
 650
 651         smc_copy_sock_settings_to_clc(smc);
 652         smc->connect_nonblock = 0;
 653         if (smc->sk.sk_state == SMC_INIT)
 654                 smc->sk.sk_state = SMC_ACTIVE;
 655
 656         return 0;
 657 }
 658
 659 /* setup for ISM connection of client */
 660 static int smc_connect_ism(struct smc_sock *smc,
 661                            struct smc_clc_msg_accept_confirm *aclc,
 662                            struct smc_init_info *ini)
 663 {
 664         int rc = 0;
 665
 666         ini->is_smcd = true;
 667         ini->ism_gid = aclc->gid;
 668         ini->srv_first_contact = aclc->hdr.flag;
 669
 670         /* there is only one lgr role for SMC-D; use server lock */
 671         mutex_lock(&smc_server_lgr_pending);
 672         rc = smc_conn_create(smc, ini);
 673         if (rc) {
 674                 mutex_unlock(&smc_server_lgr_pending);
 675                 return rc;
 676         }
 677
 678         /* Create send and receive buffers */
 679         if (smc_buf_create(smc, true))
 680                 return smc_connect_abort(smc, SMC_CLC_DECL_MEM,
 681                                          ini->cln_first_contact);
 682
 683         smc_conn_save_peer_info(smc, aclc);
 684         smc_close_init(smc);
 685         smc_rx_init(smc);
 686         smc_tx_init(smc);
 687
 688         rc = smc_clc_send_confirm(smc);
 689         if (rc)
 690                 return smc_connect_abort(smc, rc, ini->cln_first_contact);
 691         mutex_unlock(&smc_server_lgr_pending);
 692
 693         smc_copy_sock_settings_to_clc(smc);
 694         smc->connect_nonblock = 0;
 695         if (smc->sk.sk_state == SMC_INIT)
 696                 smc->sk.sk_state = SMC_ACTIVE;
 697
 698         return 0;
 699 }
 700
 701 /* perform steps before actually connecting */
 702 static int __smc_connect(struct smc_sock *smc)
 703 {
 704         bool ism_supported = false, rdma_supported = false;
 705         struct smc_clc_msg_accept_confirm aclc;
 706         struct smc_init_info ini = {0};
 707         int smc_type;
 708         int rc = 0;
 709
 710         if (smc->use_fallback)
 711                 return smc_connect_fallback(smc, smc->fallback_rsn);
 712
 713         /* if peer has not signalled SMC-capability, fall back */
 714         if (!tcp_sk(smc->clcsock->sk)->syn_smc)
 715                 return smc_connect_fallback(smc, SMC_CLC_DECL_PEERNOSMC);
 716
 717         /* IPSec connections opt out of SMC-R optimizations */
 718         if (using_ipsec(smc))
 719                 return smc_connect_decline_fallback(smc, SMC_CLC_DECL_IPSEC);
 720
 721         /* get vlan id from IP device */
 722         if (smc_vlan_by_tcpsk(smc->clcsock, &ini))
 723                 return smc_connect_decline_fallback(smc,
 724                                                     SMC_CLC_DECL_GETVLANERR);
 725
 726         /* check if there is an ism device available */
 727         if (!smc_find_ism_device(smc, &ini) &&
 728             !smc_connect_ism_vlan_setup(smc, &ini)) {
 729                 /* ISM is supported for this connection */
 730                 ism_supported = true;
 731                 smc_type = SMC_TYPE_D;
 732         }
 733
 734         /* check if there is a rdma device available */
 735         if (!smc_find_rdma_device(smc, &ini)) {
 736                 /* RDMA is supported for this connection */
 737                 rdma_supported = true;
 738                 if (ism_supported)
 739                         smc_type = SMC_TYPE_B; /* both */
 740                 else
 741                         smc_type = SMC_TYPE_R; /* only RDMA */
 742         }
 743
 744         /* if neither ISM nor RDMA are supported, fallback */
 745         if (!rdma_supported && !ism_supported)
 746                 return smc_connect_decline_fallback(smc, SMC_CLC_DECL_NOSMCDEV);
 747
 748         /* perform CLC handshake */
 749         rc = smc_connect_clc(smc, smc_type, &aclc, &ini);
 750         if (rc) {
 751                 smc_connect_ism_vlan_cleanup(smc, ism_supported, &ini);
 752                 return smc_connect_decline_fallback(smc, rc);
 753         }
 754
 755         /* depending on previous steps, connect using rdma or ism */
 756         if (rdma_supported && aclc.hdr.path == SMC_TYPE_R)
 757                 rc = smc_connect_rdma(smc, &aclc, &ini);
 758         else if (ism_supported && aclc.hdr.path == SMC_TYPE_D)
 759                 rc = smc_connect_ism(smc, &aclc, &ini);
 760         else
 761                 rc = SMC_CLC_DECL_MODEUNSUPP;
 762         if (rc) {
 763                 smc_connect_ism_vlan_cleanup(smc, ism_supported, &ini);
 764                 return smc_connect_decline_fallback(smc, rc);
 765         }
 766
 767         smc_connect_ism_vlan_cleanup(smc, ism_supported, &ini);
 768         return 0;
 769 }
 770
 771 static void smc_connect_work(struct work_struct *work)
 772 {
 773         struct smc_sock *smc = container_of(work, struct smc_sock,
 774                                             connect_work);
 775         long timeo = smc->sk.sk_sndtimeo;
 776         int rc = 0;
 777
 778         if (!timeo)
 779                 timeo = MAX_SCHEDULE_TIMEOUT;
 780         lock_sock(smc->clcsock->sk);
 781         if (smc->clcsock->sk->sk_err) {
 782                 smc->sk.sk_err = smc->clcsock->sk->sk_err;
 783         } else if ((1 << smc->clcsock->sk->sk_state) &
 784                                         (TCPF_SYN_SENT | TCP_SYN_RECV)) {
 785                 rc = sk_stream_wait_connect(smc->clcsock->sk, &timeo);
 786                 if ((rc == -EPIPE) &&
 787                     ((1 << smc->clcsock->sk->sk_state) &
 788                                         (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)))
 789                         rc = 0;
 790         }
 791         release_sock(smc->clcsock->sk);
 792         lock_sock(&smc->sk);
 793         if (rc != 0 || smc->sk.sk_err) {
 794                 smc->sk.sk_state = SMC_CLOSED;
 795                 if (rc == -EPIPE || rc == -EAGAIN)
 796                         smc->sk.sk_err = EPIPE;
 797                 else if (signal_pending(current))
 798                         smc->sk.sk_err = -sock_intr_errno(timeo);
 799                 goto out;
 800         }
 801
 802         rc = __smc_connect(smc);
 803         if (rc < 0)
 804                 smc->sk.sk_err = -rc;
 805
 806 out:
 807         if (!sock_flag(&smc->sk, SOCK_DEAD)) {
 808                 if (smc->sk.sk_err) {
 809                         smc->sk.sk_state_change(&smc->sk);
 810                 } else { /* allow polling before and after fallback decision */
 811                         smc->clcsock->sk->sk_write_space(smc->clcsock->sk);
 812                         smc->sk.sk_write_space(&smc->sk);
 813                 }
 814         }
 815         release_sock(&smc->sk);
 816 }
 817
 818 static int smc_connect(struct socket *sock, struct sockaddr *addr,
 819                        int alen, int flags)
 820 {
 821         struct sock *sk = sock->sk;
 822         struct smc_sock *smc;
 823         int rc = -EINVAL;
 824
 825         smc = smc_sk(sk);
 826
 827         /* separate smc parameter checking to be safe */
 828         if (alen < sizeof(addr->sa_family))
 829                 goto out_err;
 830         if (addr->sa_family != AF_INET && addr->sa_family != AF_INET6)
 831                 goto out_err;
 832
 833         lock_sock(sk);
 834         switch (sk->sk_state) {
 835         default:
 836                 goto out;
 837         case SMC_ACTIVE:
 838                 rc = -EISCONN;
 839                 goto out;
 840         case SMC_INIT:
 841                 rc = 0;
 842                 break;
 843         }
 844
 845         smc_copy_sock_settings_to_clc(smc);
 846         tcp_sk(smc->clcsock->sk)->syn_smc = 1;
 847         if (smc->connect_nonblock) {
 848                 rc = -EALREADY;
 849                 goto out;
 850         }
 851         rc = kernel_connect(smc->clcsock, addr, alen, flags);
 852         if (rc && rc != -EINPROGRESS)
 853                 goto out;
 854
 855         sock_hold(&smc->sk); /* sock put in passive closing */
 856         if (flags & O_NONBLOCK) {
 857                 if (schedule_work(&smc->connect_work))
 858                         smc->connect_nonblock = 1;
 859                 rc = -EINPROGRESS;
 860         } else {
 861                 rc = __smc_connect(smc);
 862                 if (rc < 0)
 863                         goto out;
 864                 else
 865                         rc = 0; /* success cases including fallback */
 866         }
 867
 868 out:
 869         release_sock(sk);
 870 out_err:
 871         return rc;
 872 }
 873
 874 static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc)
 875 {
 876         struct socket *new_clcsock = NULL;
 877         struct sock *lsk = &lsmc->sk;
 878         struct sock *new_sk;
 879         int rc = -EINVAL;
 880
 881         release_sock(lsk);
 882         new_sk = smc_sock_alloc(sock_net(lsk), NULL, lsk->sk_protocol);
 883         if (!new_sk) {
 884                 rc = -ENOMEM;
 885                 lsk->sk_err = ENOMEM;
 886                 *new_smc = NULL;
 887                 lock_sock(lsk);
 888                 goto out;
 889         }
 890         *new_smc = smc_sk(new_sk);
 891
 892         mutex_lock(&lsmc->clcsock_release_lock);
 893         if (lsmc->clcsock)
 894                 rc = kernel_accept(lsmc->clcsock, &new_clcsock, 0);
 895         mutex_unlock(&lsmc->clcsock_release_lock);
 896         lock_sock(lsk);
 897         if  (rc < 0)
 898                 lsk->sk_err = -rc;
 899         if (rc < 0 || lsk->sk_state == SMC_CLOSED) {
 900                 new_sk->sk_prot->unhash(new_sk);
 901                 if (new_clcsock)
 902                         sock_release(new_clcsock);
 903                 new_sk->sk_state = SMC_CLOSED;
 904                 sock_set_flag(new_sk, SOCK_DEAD);
 905                 sock_put(new_sk); /* final */
 906                 *new_smc = NULL;
 907                 goto out;
 908         }
 909
 910         (*new_smc)->clcsock = new_clcsock;
 911 out:
 912         return rc;
 913 }
 914
 915 /* add a just created sock to the accept queue of the listen sock as
 916  * candidate for a following socket accept call from user space
 917  */
 918 static void smc_accept_enqueue(struct sock *parent, struct sock *sk)
 919 {
 920         struct smc_sock *par = smc_sk(parent);
 921
 922         sock_hold(sk); /* sock_put in smc_accept_unlink () */
 923         spin_lock(&par->accept_q_lock);
 924         list_add_tail(&smc_sk(sk)->accept_q, &par->accept_q);
 925         spin_unlock(&par->accept_q_lock);
 926         sk_acceptq_added(parent);
 927 }
 928
 929 /* remove a socket from the accept queue of its parental listening socket */
 930 static void smc_accept_unlink(struct sock *sk)
 931 {
 932         struct smc_sock *par = smc_sk(sk)->listen_smc;
 933
 934         spin_lock(&par->accept_q_lock);
 935         list_del_init(&smc_sk(sk)->accept_q);
 936         spin_unlock(&par->accept_q_lock);
 937         sk_acceptq_removed(&smc_sk(sk)->listen_smc->sk);
 938         sock_put(sk); /* sock_hold in smc_accept_enqueue */
 939 }
 940
 941 /* remove a sock from the accept queue to bind it to a new socket created
 942  * for a socket accept call from user space
 943  */
 944 struct sock *smc_accept_dequeue(struct sock *parent,
 945                                 struct socket *new_sock)
 946 {
 947         struct smc_sock *isk, *n;
 948         struct sock *new_sk;
 949
 950         list_for_each_entry_safe(isk, n, &smc_sk(parent)->accept_q, accept_q) {
 951                 new_sk = (struct sock *)isk;
 952
 953                 smc_accept_unlink(new_sk);
 954                 if (new_sk->sk_state == SMC_CLOSED) {
 955                         new_sk->sk_prot->unhash(new_sk);
 956                         if (isk->clcsock) {
 957                                 sock_release(isk->clcsock);
 958                                 isk->clcsock = NULL;
 959                         }
 960                         sock_put(new_sk); /* final */
 961                         continue;
 962                 }
 963                 if (new_sock) {
 964                         sock_graft(new_sk, new_sock);
 965                         if (isk->use_fallback) {
 966                                 smc_sk(new_sk)->clcsock->file = new_sock->file;
 967                                 isk->clcsock->file->private_data = isk->clcsock;
 968                         }
 969                 }
 970                 return new_sk;
 971         }
 972         return NULL;
 973 }
 974
 975 /* clean up for a created but never accepted sock */
 976 void smc_close_non_accepted(struct sock *sk)
 977 {
 978         struct smc_sock *smc = smc_sk(sk);
 979
 980         lock_sock(sk);
 981         if (!sk->sk_lingertime)
 982                 /* wait for peer closing */
 983                 sk->sk_lingertime = SMC_MAX_STREAM_WAIT_TIMEOUT;
 984         __smc_release(smc);
 985         release_sock(sk);
 986         sock_put(sk); /* final sock_put */
 987 }
 988
 989 static int smc_serv_conf_first_link(struct smc_sock *smc)
 990 {
 991         struct net *net = sock_net(smc->clcsock->sk);
 992         struct smc_link_group *lgr = smc->conn.lgr;
 993         struct smc_link *link;
 994         int rest;
 995         int rc;
 996
 997         link = &lgr->lnk[SMC_SINGLE_LINK];
 998
 999         if (smc_reg_rmb(link, smc->conn.rmb_desc, false))
1000                 return SMC_CLC_DECL_ERR_REGRMB;
1001
1002         /* send CONFIRM LINK request to client over the RoCE fabric */
1003         rc = smc_llc_send_confirm_link(link, SMC_LLC_REQ);
1004         if (rc < 0)
1005                 return SMC_CLC_DECL_TIMEOUT_CL;
1006
1007         /* receive CONFIRM LINK response from client over the RoCE fabric */
1008         rest = wait_for_completion_interruptible_timeout(
1009                 &link->llc_confirm_resp,
1010                 SMC_LLC_WAIT_FIRST_TIME);
1011         if (rest <= 0) {
1012                 struct smc_clc_msg_decline dclc;
1013
1014                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
1015                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
1016                 return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
1017         }
1018
1019         if (link->llc_confirm_resp_rc)
1020                 return SMC_CLC_DECL_RMBE_EC;
1021
1022         /* send ADD LINK request to client over the RoCE fabric */
1023         rc = smc_llc_send_add_link(link,
1024                                    link->smcibdev->mac[link->ibport - 1],
1025                                    link->gid, SMC_LLC_REQ);
1026         if (rc < 0)
1027                 return SMC_CLC_DECL_TIMEOUT_AL;
1028
1029         /* receive ADD LINK response from client over the RoCE fabric */
1030         rest = wait_for_completion_interruptible_timeout(&link->llc_add_resp,
1031                                                          SMC_LLC_WAIT_TIME);
1032         if (rest <= 0) {
1033                 struct smc_clc_msg_decline dclc;
1034
1035                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
1036                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
1037                 return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_AL : rc;
1038         }
1039
1040         smc_llc_link_active(link, net->ipv4.sysctl_tcp_keepalive_time);
1041
1042         return 0;
1043 }
1044
1045 /* listen worker: finish */
1046 static void smc_listen_out(struct smc_sock *new_smc)
1047 {
1048         struct smc_sock *lsmc = new_smc->listen_smc;
1049         struct sock *newsmcsk = &new_smc->sk;
1050
1051         if (lsmc->sk.sk_state == SMC_LISTEN) {
1052                 lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING);
1053                 smc_accept_enqueue(&lsmc->sk, newsmcsk);
1054                 release_sock(&lsmc->sk);
1055         } else { /* no longer listening */
1056                 smc_close_non_accepted(newsmcsk);
1057         }
1058
1059         /* Wake up accept */
1060         lsmc->sk.sk_data_ready(&lsmc->sk);
1061         sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */
1062 }
1063
1064 /* listen worker: finish in state connected */
1065 static void smc_listen_out_connected(struct smc_sock *new_smc)
1066 {
1067         struct sock *newsmcsk = &new_smc->sk;
1068
1069         sk_refcnt_debug_inc(newsmcsk);
1070         if (newsmcsk->sk_state == SMC_INIT)
1071                 newsmcsk->sk_state = SMC_ACTIVE;
1072
1073         smc_listen_out(new_smc);
1074 }
1075
1076 /* listen worker: finish in error state */
1077 static void smc_listen_out_err(struct smc_sock *new_smc)
1078 {
1079         struct sock *newsmcsk = &new_smc->sk;
1080
1081         if (newsmcsk->sk_state == SMC_INIT)
1082                 sock_put(&new_smc->sk); /* passive closing */
1083         newsmcsk->sk_state = SMC_CLOSED;
1084         smc_conn_free(&new_smc->conn);
1085
1086         smc_listen_out(new_smc);
1087 }
1088
1089 /* listen worker: decline and fall back if possible */
1090 static void smc_listen_decline(struct smc_sock *new_smc, int reason_code,
1091                                int local_contact)
1092 {
1093         /* RDMA setup failed, switch back to TCP */
1094         if (local_contact == SMC_FIRST_CONTACT)
1095                 smc_lgr_forget(new_smc->conn.lgr);
1096         if (reason_code < 0) { /* error, no fallback possible */
1097                 smc_listen_out_err(new_smc);
1098                 return;
1099         }
1100         smc_conn_free(&new_smc->conn);
1101         smc_switch_to_fallback(new_smc);
1102         new_smc->fallback_rsn = reason_code;
1103         if (reason_code && reason_code != SMC_CLC_DECL_PEERDECL) {
1104                 if (smc_clc_send_decline(new_smc, reason_code) < 0) {
1105                         smc_listen_out_err(new_smc);
1106                         return;
1107                 }
1108         }
1109         smc_listen_out_connected(new_smc);
1110 }
1111
1112 /* listen worker: check prefixes */
1113 static int smc_listen_prfx_check(struct smc_sock *new_smc,
1114                                  struct smc_clc_msg_proposal *pclc)
1115 {
1116         struct smc_clc_msg_proposal_prefix *pclc_prfx;
1117         struct socket *newclcsock = new_smc->clcsock;
1118
1119         pclc_prfx = smc_clc_proposal_get_prefix(pclc);
1120         if (smc_clc_prfx_match(newclcsock, pclc_prfx))
1121                 return SMC_CLC_DECL_DIFFPREFIX;
1122
1123         return 0;
1124 }
1125
1126 /* listen worker: initialize connection and buffers */
1127 static int smc_listen_rdma_init(struct smc_sock *new_smc,
1128                                 struct smc_init_info *ini)
1129 {
1130         int rc;
1131
1132         /* allocate connection / link group */
1133         rc = smc_conn_create(new_smc, ini);
1134         if (rc)
1135                 return rc;
1136
1137         /* create send buffer and rmb */
1138         if (smc_buf_create(new_smc, false))
1139                 return SMC_CLC_DECL_MEM;
1140
1141         return 0;
1142 }
1143
1144 /* listen worker: initialize connection and buffers for SMC-D */
1145 static int smc_listen_ism_init(struct smc_sock *new_smc,
1146                                struct smc_clc_msg_proposal *pclc,
1147                                struct smc_init_info *ini)
1148 {
1149         struct smc_clc_msg_smcd *pclc_smcd;
1150         int rc;
1151
1152         pclc_smcd = smc_get_clc_msg_smcd(pclc);
1153         ini->ism_gid = pclc_smcd->gid;
1154         rc = smc_conn_create(new_smc, ini);
1155         if (rc)
1156                 return rc;
1157
1158         /* Check if peer can be reached via ISM device */
1159         if (smc_ism_cantalk(new_smc->conn.lgr->peer_gid,
1160                             new_smc->conn.lgr->vlan_id,
1161                             new_smc->conn.lgr->smcd)) {
1162                 if (ini->cln_first_contact == SMC_FIRST_CONTACT)
1163                         smc_lgr_forget(new_smc->conn.lgr);
1164                 smc_conn_free(&new_smc->conn);
1165                 return SMC_CLC_DECL_SMCDNOTALK;
1166         }
1167
1168         /* Create send and receive buffers */
1169         if (smc_buf_create(new_smc, true)) {
1170                 if (ini->cln_first_contact == SMC_FIRST_CONTACT)
1171                         smc_lgr_forget(new_smc->conn.lgr);
1172                 smc_conn_free(&new_smc->conn);
1173                 return SMC_CLC_DECL_MEM;
1174         }
1175
1176         return 0;
1177 }
1178
1179 /* listen worker: register buffers */
1180 static int smc_listen_rdma_reg(struct smc_sock *new_smc, int local_contact)
1181 {
1182         struct smc_link *link = &new_smc->conn.lgr->lnk[SMC_SINGLE_LINK];
1183
1184         if (local_contact != SMC_FIRST_CONTACT) {
1185                 if (smc_reg_rmb(link, new_smc->conn.rmb_desc, true))
1186                         return SMC_CLC_DECL_ERR_REGRMB;
1187         }
1188         smc_rmb_sync_sg_for_device(&new_smc->conn);
1189
1190         return 0;
1191 }
1192
1193 /* listen worker: finish RDMA setup */
1194 static int smc_listen_rdma_finish(struct smc_sock *new_smc,
1195                                   struct smc_clc_msg_accept_confirm *cclc,
1196                                   int local_contact)
1197 {
1198         struct smc_link *link = &new_smc->conn.lgr->lnk[SMC_SINGLE_LINK];
1199         int reason_code = 0;
1200
1201         if (local_contact == SMC_FIRST_CONTACT)
1202                 smc_link_save_peer_info(link, cclc);
1203
1204         if (smc_rmb_rtoken_handling(&new_smc->conn, cclc)) {
1205                 reason_code = SMC_CLC_DECL_ERR_RTOK;
1206                 goto decline;
1207         }
1208
1209         if (local_contact == SMC_FIRST_CONTACT) {
1210                 if (smc_ib_ready_link(link)) {
1211                         reason_code = SMC_CLC_DECL_ERR_RDYLNK;
1212                         goto decline;
1213                 }
1214                 /* QP confirmation over RoCE fabric */
1215                 reason_code = smc_serv_conf_first_link(new_smc);
1216                 if (reason_code)
1217                         goto decline;
1218         }
1219         return 0;
1220
1221 decline:
1222         smc_listen_decline(new_smc, reason_code, local_contact);
1223         return reason_code;
1224 }
1225
1226 /* setup for RDMA connection of server */
1227 static void smc_listen_work(struct work_struct *work)
1228 {
1229         struct smc_sock *new_smc = container_of(work, struct smc_sock,
1230                                                 smc_listen_work);
1231         struct socket *newclcsock = new_smc->clcsock;
1232         struct smc_clc_msg_accept_confirm cclc;
1233         struct smc_clc_msg_proposal *pclc;
1234         struct smc_init_info ini = {0};
1235         bool ism_supported = false;
1236         u8 buf[SMC_CLC_MAX_LEN];
1237         int rc = 0;
1238
1239         if (new_smc->listen_smc->sk.sk_state != SMC_LISTEN)
1240                 return smc_listen_out_err(new_smc);
1241
1242         if (new_smc->use_fallback) {
1243                 smc_listen_out_connected(new_smc);
1244                 return;
1245         }
1246
1247         /* check if peer is smc capable */
1248         if (!tcp_sk(newclcsock->sk)->syn_smc) {
1249                 smc_switch_to_fallback(new_smc);
1250                 new_smc->fallback_rsn = SMC_CLC_DECL_PEERNOSMC;
1251                 smc_listen_out_connected(new_smc);
1252                 return;
1253         }
1254
1255         /* do inband token exchange -
1256          * wait for and receive SMC Proposal CLC message
1257          */
1258         pclc = (struct smc_clc_msg_proposal *)&buf;
1259         rc = smc_clc_wait_msg(new_smc, pclc, SMC_CLC_MAX_LEN,
1260                               SMC_CLC_PROPOSAL, CLC_WAIT_TIME);
1261         if (rc)
1262                 goto out_decl;
1263
1264         /* IPSec connections opt out of SMC-R optimizations */
1265         if (using_ipsec(new_smc)) {
1266                 rc = SMC_CLC_DECL_IPSEC;
1267                 goto out_decl;
1268         }
1269
1270         /* check for matching IP prefix and subnet length */
1271         rc = smc_listen_prfx_check(new_smc, pclc);
1272         if (rc)
1273                 goto out_decl;
1274
1275         /* get vlan id from IP device */
1276         if (smc_vlan_by_tcpsk(new_smc->clcsock, &ini)) {
1277                 rc = SMC_CLC_DECL_GETVLANERR;
1278                 goto out_decl;
1279         }
1280
1281         mutex_lock(&smc_server_lgr_pending);
1282         smc_close_init(new_smc);
1283         smc_rx_init(new_smc);
1284         smc_tx_init(new_smc);
1285
1286         /* check if ISM is available */
1287         if (pclc->hdr.path == SMC_TYPE_D || pclc->hdr.path == SMC_TYPE_B) {
1288                 ini.is_smcd = true; /* prepare ISM check */
1289                 rc = smc_find_ism_device(new_smc, &ini);
1290                 if (!rc)
1291                         rc = smc_listen_ism_init(new_smc, pclc, &ini);
1292                 if (!rc)
1293                         ism_supported = true;
1294                 else if (pclc->hdr.path == SMC_TYPE_D)
1295                         goto out_unlock; /* skip RDMA and decline */
1296         }
1297
1298         /* check if RDMA is available */
1299         if (!ism_supported) { /* SMC_TYPE_R or SMC_TYPE_B */
1300                 /* prepare RDMA check */
1301                 ini.is_smcd = false;
1302                 ini.ism_dev = NULL;
1303                 ini.ib_lcl = &pclc->lcl;
1304                 rc = smc_find_rdma_device(new_smc, &ini);
1305                 if (rc) {
1306                         /* no RDMA device found */
1307                         if (pclc->hdr.path == SMC_TYPE_B)
1308                                 /* neither ISM nor RDMA device found */
1309                                 rc = SMC_CLC_DECL_NOSMCDEV;
1310                         goto out_unlock;
1311                 }
1312                 rc = smc_listen_rdma_init(new_smc, &ini);
1313                 if (rc)
1314                         goto out_unlock;
1315                 rc = smc_listen_rdma_reg(new_smc, ini.cln_first_contact);
1316                 if (rc)
1317                         goto out_unlock;
1318         }
1319
1320         /* send SMC Accept CLC message */
1321         rc = smc_clc_send_accept(new_smc, ini.cln_first_contact);
1322         if (rc)
1323                 goto out_unlock;
1324
1325         /* SMC-D does not need this lock any more */
1326         if (ism_supported)
1327                 mutex_unlock(&smc_server_lgr_pending);
1328
1329         /* receive SMC Confirm CLC message */
1330         rc = smc_clc_wait_msg(new_smc, &cclc, sizeof(cclc),
1331                               SMC_CLC_CONFIRM, CLC_WAIT_TIME);
1332         if (rc) {
1333                 if (!ism_supported)
1334                         goto out_unlock;
1335                 goto out_decl;
1336         }
1337
1338         /* finish worker */
1339         if (!ism_supported) {
1340                 rc = smc_listen_rdma_finish(new_smc, &cclc,
1341                                             ini.cln_first_contact);
1342                 mutex_unlock(&smc_server_lgr_pending);
1343                 if (rc)
1344                         return;
1345         }
1346         smc_conn_save_peer_info(new_smc, &cclc);
1347         smc_listen_out_connected(new_smc);
1348         return;
1349
1350 out_unlock:
1351         mutex_unlock(&smc_server_lgr_pending);
1352 out_decl:
1353         smc_listen_decline(new_smc, rc, ini.cln_first_contact);
1354 }
1355
1356 static void smc_tcp_listen_work(struct work_struct *work)
1357 {
1358         struct smc_sock *lsmc = container_of(work, struct smc_sock,
1359                                              tcp_listen_work);
1360         struct sock *lsk = &lsmc->sk;
1361         struct smc_sock *new_smc;
1362         int rc = 0;
1363
1364         lock_sock(lsk);
1365         while (lsk->sk_state == SMC_LISTEN) {
1366                 rc = smc_clcsock_accept(lsmc, &new_smc);
1367                 if (rc)
1368                         goto out;
1369                 if (!new_smc)
1370                         continue;
1371
1372                 new_smc->listen_smc = lsmc;
1373                 new_smc->use_fallback = lsmc->use_fallback;
1374                 new_smc->fallback_rsn = lsmc->fallback_rsn;
1375                 sock_hold(lsk); /* sock_put in smc_listen_work */
1376                 INIT_WORK(&new_smc->smc_listen_work, smc_listen_work);
1377                 smc_copy_sock_settings_to_smc(new_smc);
1378                 new_smc->sk.sk_sndbuf = lsmc->sk.sk_sndbuf;
1379                 new_smc->sk.sk_rcvbuf = lsmc->sk.sk_rcvbuf;
1380                 sock_hold(&new_smc->sk); /* sock_put in passive closing */
1381                 if (!schedule_work(&new_smc->smc_listen_work))
1382                         sock_put(&new_smc->sk);
1383         }
1384
1385 out:
1386         release_sock(lsk);
1387         sock_put(&lsmc->sk); /* sock_hold in smc_listen */
1388 }
1389
1390 static int smc_listen(struct socket *sock, int backlog)
1391 {
1392         struct sock *sk = sock->sk;
1393         struct smc_sock *smc;
1394         int rc;
1395
1396         smc = smc_sk(sk);
1397         lock_sock(sk);
1398
1399         rc = -EINVAL;
1400         if ((sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) ||
1401             smc->connect_nonblock)
1402                 goto out;
1403
1404         rc = 0;
1405         if (sk->sk_state == SMC_LISTEN) {
1406                 sk->sk_max_ack_backlog = backlog;
1407                 goto out;
1408         }
1409         /* some socket options are handled in core, so we could not apply
1410          * them to the clc socket -- copy smc socket options to clc socket
1411          */
1412         smc_copy_sock_settings_to_clc(smc);
1413         if (!smc->use_fallback)
1414                 tcp_sk(smc->clcsock->sk)->syn_smc = 1;
1415
1416         rc = kernel_listen(smc->clcsock, backlog);
1417         if (rc)
1418                 goto out;
1419         sk->sk_max_ack_backlog = backlog;
1420         sk->sk_ack_backlog = 0;
1421         sk->sk_state = SMC_LISTEN;
1422         sock_hold(sk); /* sock_hold in tcp_listen_worker */
1423         if (!schedule_work(&smc->tcp_listen_work))
1424                 sock_put(sk);
1425
1426 out:
1427         release_sock(sk);
1428         return rc;
1429 }
1430
1431 static int smc_accept(struct socket *sock, struct socket *new_sock,
1432                       int flags, bool kern)
1433 {
1434         struct sock *sk = sock->sk, *nsk;
1435         DECLARE_WAITQUEUE(wait, current);
1436         struct smc_sock *lsmc;
1437         long timeo;
1438         int rc = 0;
1439
1440         lsmc = smc_sk(sk);
1441         sock_hold(sk); /* sock_put below */
1442         lock_sock(sk);
1443
1444         if (lsmc->sk.sk_state != SMC_LISTEN) {
1445                 rc = -EINVAL;
1446                 release_sock(sk);
1447                 goto out;
1448         }
1449
1450         /* Wait for an incoming connection */
1451         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
1452         add_wait_queue_exclusive(sk_sleep(sk), &wait);
1453         while (!(nsk = smc_accept_dequeue(sk, new_sock))) {
1454                 set_current_state(TASK_INTERRUPTIBLE);
1455                 if (!timeo) {
1456                         rc = -EAGAIN;
1457                         break;
1458                 }
1459                 release_sock(sk);
1460                 timeo = schedule_timeout(timeo);
1461                 /* wakeup by sk_data_ready in smc_listen_work() */
1462                 sched_annotate_sleep();
1463                 lock_sock(sk);
1464                 if (signal_pending(current)) {
1465                         rc = sock_intr_errno(timeo);
1466                         break;
1467                 }
1468         }
1469         set_current_state(TASK_RUNNING);
1470         remove_wait_queue(sk_sleep(sk), &wait);
1471
1472         if (!rc)
1473                 rc = sock_error(nsk);
1474         release_sock(sk);
1475         if (rc)
1476                 goto out;
1477
1478         if (lsmc->sockopt_defer_accept && !(flags & O_NONBLOCK)) {
1479                 /* wait till data arrives on the socket */
1480                 timeo = msecs_to_jiffies(lsmc->sockopt_defer_accept *
1481                                                                 MSEC_PER_SEC);
1482                 if (smc_sk(nsk)->use_fallback) {
1483                         struct sock *clcsk = smc_sk(nsk)->clcsock->sk;
1484
1485                         lock_sock(clcsk);
1486                         if (skb_queue_empty(&clcsk->sk_receive_queue))
1487                                 sk_wait_data(clcsk, &timeo, NULL);
1488                         release_sock(clcsk);
1489                 } else if (!atomic_read(&smc_sk(nsk)->conn.bytes_to_rcv)) {
1490                         lock_sock(nsk);
1491                         smc_rx_wait(smc_sk(nsk), &timeo, smc_rx_data_available);
1492                         release_sock(nsk);
1493                 }
1494         }
1495
1496 out:
1497         sock_put(sk); /* sock_hold above */
1498         return rc;
1499 }
1500
1501 static int smc_getname(struct socket *sock, struct sockaddr *addr,
1502                        int peer)
1503 {
1504         struct smc_sock *smc;
1505
1506         if (peer && (sock->sk->sk_state != SMC_ACTIVE) &&
1507             (sock->sk->sk_state != SMC_APPCLOSEWAIT1))
1508                 return -ENOTCONN;
1509
1510         smc = smc_sk(sock->sk);
1511
1512         return smc->clcsock->ops->getname(smc->clcsock, addr, peer);
1513 }
1514
1515 static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1516 {
1517         struct sock *sk = sock->sk;
1518         struct smc_sock *smc;
1519         int rc = -EPIPE;
1520
1521         smc = smc_sk(sk);
1522         lock_sock(sk);
1523         if ((sk->sk_state != SMC_ACTIVE) &&
1524             (sk->sk_state != SMC_APPCLOSEWAIT1) &&
1525             (sk->sk_state != SMC_INIT))
1526                 goto out;
1527
1528         if (msg->msg_flags & MSG_FASTOPEN) {
1529                 if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
1530                         smc_switch_to_fallback(smc);
1531                         smc->fallback_rsn = SMC_CLC_DECL_OPTUNSUPP;
1532                 } else {
1533                         rc = -EINVAL;
1534                         goto out;
1535                 }
1536         }
1537
1538         if (smc->use_fallback)
1539                 rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len);
1540         else
1541                 rc = smc_tx_sendmsg(smc, msg, len);
1542 out:
1543         release_sock(sk);
1544         return rc;
1545 }
1546
1547 static int smc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
1548                        int flags)
1549 {
1550         struct sock *sk = sock->sk;
1551         struct smc_sock *smc;
1552         int rc = -ENOTCONN;
1553
1554         smc = smc_sk(sk);
1555         lock_sock(sk);
1556         if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
1557                 /* socket was connected before, no more data to read */
1558                 rc = 0;
1559                 goto out;
1560         }
1561         if ((sk->sk_state == SMC_INIT) ||
1562             (sk->sk_state == SMC_LISTEN) ||
1563             (sk->sk_state == SMC_CLOSED))
1564                 goto out;
1565
1566         if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
1567                 rc = 0;
1568                 goto out;
1569         }
1570
1571         if (smc->use_fallback) {
1572                 rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags);
1573         } else {
1574                 msg->msg_namelen = 0;
1575                 rc = smc_rx_recvmsg(smc, msg, NULL, len, flags);
1576         }
1577
1578 out:
1579         release_sock(sk);
1580         return rc;
1581 }
1582
1583 static __poll_t smc_accept_poll(struct sock *parent)
1584 {
1585         struct smc_sock *isk = smc_sk(parent);
1586         __poll_t mask = 0;
1587
1588         spin_lock(&isk->accept_q_lock);
1589         if (!list_empty(&isk->accept_q))
1590                 mask = EPOLLIN | EPOLLRDNORM;
1591         spin_unlock(&isk->accept_q_lock);
1592
1593         return mask;
1594 }
1595
1596 static __poll_t smc_poll(struct file *file, struct socket *sock,
1597                              poll_table *wait)
1598 {
1599         struct sock *sk = sock->sk;
1600         struct smc_sock *smc;
1601         __poll_t mask = 0;
1602
1603         if (!sk)
1604                 return EPOLLNVAL;
1605
1606         smc = smc_sk(sock->sk);
1607         if (smc->use_fallback) {
1608                 /* delegate to CLC child sock */
1609                 mask = smc->clcsock->ops->poll(file, smc->clcsock, wait);
1610                 sk->sk_err = smc->clcsock->sk->sk_err;
1611         } else {
1612                 if (sk->sk_state != SMC_CLOSED)
1613                         sock_poll_wait(file, sock, wait);
1614                 if (sk->sk_err)
1615                         mask |= EPOLLERR;
1616                 if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
1617                     (sk->sk_state == SMC_CLOSED))
1618                         mask |= EPOLLHUP;
1619                 if (sk->sk_state == SMC_LISTEN) {
1620                         /* woken up by sk_data_ready in smc_listen_work() */
1621                         mask |= smc_accept_poll(sk);
1622                 } else if (smc->use_fallback) { /* as result of connect_work()*/
1623                         mask |= smc->clcsock->ops->poll(file, smc->clcsock,
1624                                                            wait);
1625                         sk->sk_err = smc->clcsock->sk->sk_err;
1626                 } else {
1627                         if ((sk->sk_state != SMC_INIT &&
1628                              atomic_read(&smc->conn.sndbuf_space)) ||
1629                             sk->sk_shutdown & SEND_SHUTDOWN) {
1630                                 mask |= EPOLLOUT | EPOLLWRNORM;
1631                         } else {
1632                                 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1633                                 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1634                         }
1635                         if (atomic_read(&smc->conn.bytes_to_rcv))
1636                                 mask |= EPOLLIN | EPOLLRDNORM;
1637                         if (sk->sk_shutdown & RCV_SHUTDOWN)
1638                                 mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
1639                         if (sk->sk_state == SMC_APPCLOSEWAIT1)
1640                                 mask |= EPOLLIN;
1641                         if (smc->conn.urg_state == SMC_URG_VALID)
1642                                 mask |= EPOLLPRI;
1643                 }
1644         }
1645
1646         return mask;
1647 }
1648
1649 static int smc_shutdown(struct socket *sock, int how)
1650 {
1651         struct sock *sk = sock->sk;
1652         struct smc_sock *smc;
1653         int rc = -EINVAL;
1654         int rc1 = 0;
1655
1656         smc = smc_sk(sk);
1657
1658         if ((how < SHUT_RD) || (how > SHUT_RDWR))
1659                 return rc;
1660
1661         lock_sock(sk);
1662
1663         rc = -ENOTCONN;
1664         if ((sk->sk_state != SMC_ACTIVE) &&
1665             (sk->sk_state != SMC_PEERCLOSEWAIT1) &&
1666             (sk->sk_state != SMC_PEERCLOSEWAIT2) &&
1667             (sk->sk_state != SMC_APPCLOSEWAIT1) &&
1668             (sk->sk_state != SMC_APPCLOSEWAIT2) &&
1669             (sk->sk_state != SMC_APPFINCLOSEWAIT))
1670                 goto out;
1671         if (smc->use_fallback) {
1672                 rc = kernel_sock_shutdown(smc->clcsock, how);
1673                 sk->sk_shutdown = smc->clcsock->sk->sk_shutdown;
1674                 if (sk->sk_shutdown == SHUTDOWN_MASK)
1675                         sk->sk_state = SMC_CLOSED;
1676                 goto out;
1677         }
1678         switch (how) {
1679         case SHUT_RDWR:         /* shutdown in both directions */
1680                 rc = smc_close_active(smc);
1681                 break;
1682         case SHUT_WR:
1683                 rc = smc_close_shutdown_write(smc);
1684                 break;
1685         case SHUT_RD:
1686                 rc = 0;
1687                 /* nothing more to do because peer is not involved */
1688                 break;
1689         }
1690         if (smc->clcsock)
1691                 rc1 = kernel_sock_shutdown(smc->clcsock, how);
1692         /* map sock_shutdown_cmd constants to sk_shutdown value range */
1693         sk->sk_shutdown |= how + 1;
1694
1695 out:
1696         release_sock(sk);
1697         return rc ? rc : rc1;
1698 }
1699
1700 static int smc_setsockopt(struct socket *sock, int level, int optname,
1701                           char __user *optval, unsigned int optlen)
1702 {
1703         struct sock *sk = sock->sk;
1704         struct smc_sock *smc;
1705         int val, rc;
1706
1707         smc = smc_sk(sk);
1708
1709         /* generic setsockopts reaching us here always apply to the
1710          * CLC socket
1711          */
1712         rc = smc->clcsock->ops->setsockopt(smc->clcsock, level, optname,
1713                                            optval, optlen);
1714         if (smc->clcsock->sk->sk_err) {
1715                 sk->sk_err = smc->clcsock->sk->sk_err;
1716                 sk->sk_error_report(sk);
1717         }
1718         if (rc)
1719                 return rc;
1720
1721         if (optlen < sizeof(int))
1722                 return -EINVAL;
1723         if (get_user(val, (int __user *)optval))
1724                 return -EFAULT;
1725
1726         lock_sock(sk);
1727         switch (optname) {
1728         case TCP_ULP:
1729         case TCP_FASTOPEN:
1730         case TCP_FASTOPEN_CONNECT:
1731         case TCP_FASTOPEN_KEY:
1732         case TCP_FASTOPEN_NO_COOKIE:
1733                 /* option not supported by SMC */
1734                 if (sk->sk_state == SMC_INIT) {
1735                         smc_switch_to_fallback(smc);
1736                         smc->fallback_rsn = SMC_CLC_DECL_OPTUNSUPP;
1737                 } else {
1738                         if (!smc->use_fallback)
1739                                 rc = -EINVAL;
1740                 }
1741                 break;
1742         case TCP_NODELAY:
1743                 if (sk->sk_state != SMC_INIT &&
1744                     sk->sk_state != SMC_LISTEN &&
1745                     sk->sk_state != SMC_CLOSED) {
1746                         if (val && !smc->use_fallback)
1747                                 mod_delayed_work(system_wq, &smc->conn.tx_work,
1748                                                  0);
1749                 }
1750                 break;
1751         case TCP_CORK:
1752                 if (sk->sk_state != SMC_INIT &&
1753                     sk->sk_state != SMC_LISTEN &&
1754                     sk->sk_state != SMC_CLOSED) {
1755                         if (!val && !smc->use_fallback)
1756                                 mod_delayed_work(system_wq, &smc->conn.tx_work,
1757                                                  0);
1758                 }
1759                 break;
1760         case TCP_DEFER_ACCEPT:
1761                 smc->sockopt_defer_accept = val;
1762                 break;
1763         default:
1764                 break;
1765         }
1766         release_sock(sk);
1767
1768         return rc;
1769 }
1770
1771 static int smc_getsockopt(struct socket *sock, int level, int optname,
1772                           char __user *optval, int __user *optlen)
1773 {
1774         struct smc_sock *smc;
1775
1776         smc = smc_sk(sock->sk);
1777         /* socket options apply to the CLC socket */
1778         return smc->clcsock->ops->getsockopt(smc->clcsock, level, optname,
1779                                              optval, optlen);
1780 }
1781
1782 static int smc_ioctl(struct socket *sock, unsigned int cmd,
1783                      unsigned long arg)
1784 {
1785         union smc_host_cursor cons, urg;
1786         struct smc_connection *conn;
1787         struct smc_sock *smc;
1788         int answ;
1789
1790         smc = smc_sk(sock->sk);
1791         conn = &smc->conn;
1792         lock_sock(&smc->sk);
1793         if (smc->use_fallback) {
1794                 if (!smc->clcsock) {
1795                         release_sock(&smc->sk);
1796                         return -EBADF;
1797                 }
1798                 answ = smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg);
1799                 release_sock(&smc->sk);
1800                 return answ;
1801         }
1802         switch (cmd) {
1803         case SIOCINQ: /* same as FIONREAD */
1804                 if (smc->sk.sk_state == SMC_LISTEN) {
1805                         release_sock(&smc->sk);
1806                         return -EINVAL;
1807                 }
1808                 if (smc->sk.sk_state == SMC_INIT ||
1809                     smc->sk.sk_state == SMC_CLOSED)
1810                         answ = 0;
1811                 else
1812                         answ = atomic_read(&smc->conn.bytes_to_rcv);
1813                 break;
1814         case SIOCOUTQ:
1815                 /* output queue size (not send + not acked) */
1816                 if (smc->sk.sk_state == SMC_LISTEN) {
1817                         release_sock(&smc->sk);
1818                         return -EINVAL;
1819                 }
1820                 if (smc->sk.sk_state == SMC_INIT ||
1821                     smc->sk.sk_state == SMC_CLOSED)
1822                         answ = 0;
1823                 else
1824                         answ = smc->conn.sndbuf_desc->len -
1825                                         atomic_read(&smc->conn.sndbuf_space);
1826                 break;
1827         case SIOCOUTQNSD:
1828                 /* output queue size (not send only) */
1829                 if (smc->sk.sk_state == SMC_LISTEN) {
1830                         release_sock(&smc->sk);
1831                         return -EINVAL;
1832                 }
1833                 if (smc->sk.sk_state == SMC_INIT ||
1834                     smc->sk.sk_state == SMC_CLOSED)
1835                         answ = 0;
1836                 else
1837                         answ = smc_tx_prepared_sends(&smc->conn);
1838                 break;
1839         case SIOCATMARK:
1840                 if (smc->sk.sk_state == SMC_LISTEN) {
1841                         release_sock(&smc->sk);
1842                         return -EINVAL;
1843                 }
1844                 if (smc->sk.sk_state == SMC_INIT ||
1845                     smc->sk.sk_state == SMC_CLOSED) {
1846                         answ = 0;
1847                 } else {
1848                         smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
1849                         smc_curs_copy(&urg, &conn->urg_curs, conn);
1850                         answ = smc_curs_diff(conn->rmb_desc->len,
1851                                              &cons, &urg) == 1;
1852                 }
1853                 break;
1854         default:
1855                 release_sock(&smc->sk);
1856                 return -ENOIOCTLCMD;
1857         }
1858         release_sock(&smc->sk);
1859
1860         return put_user(answ, (int __user *)arg);
1861 }
1862
1863 static ssize_t smc_sendpage(struct socket *sock, struct page *page,
1864                             int offset, size_t size, int flags)
1865 {
1866         struct sock *sk = sock->sk;
1867         struct smc_sock *smc;
1868         int rc = -EPIPE;
1869
1870         smc = smc_sk(sk);
1871         lock_sock(sk);
1872         if (sk->sk_state != SMC_ACTIVE) {
1873                 release_sock(sk);
1874                 goto out;
1875         }
1876         release_sock(sk);
1877         if (smc->use_fallback)
1878                 rc = kernel_sendpage(smc->clcsock, page, offset,
1879                                      size, flags);
1880         else
1881                 rc = sock_no_sendpage(sock, page, offset, size, flags);
1882
1883 out:
1884         return rc;
1885 }
1886
1887 /* Map the affected portions of the rmbe into an spd, note the number of bytes
1888  * to splice in conn->splice_pending, and press 'go'. Delays consumer cursor
1889  * updates till whenever a respective page has been fully processed.
1890  * Note that subsequent recv() calls have to wait till all splice() processing
1891  * completed.
1892  */
1893 static ssize_t smc_splice_read(struct socket *sock, loff_t *ppos,
1894                                struct pipe_inode_info *pipe, size_t len,
1895                                unsigned int flags)
1896 {
1897         struct sock *sk = sock->sk;
1898         struct smc_sock *smc;
1899         int rc = -ENOTCONN;
1900
1901         smc = smc_sk(sk);
1902         lock_sock(sk);
1903         if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
1904                 /* socket was connected before, no more data to read */
1905                 rc = 0;
1906                 goto out;
1907         }
1908         if (sk->sk_state == SMC_INIT ||
1909             sk->sk_state == SMC_LISTEN ||
1910             sk->sk_state == SMC_CLOSED)
1911                 goto out;
1912
1913         if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
1914                 rc = 0;
1915                 goto out;
1916         }
1917
1918         if (smc->use_fallback) {
1919                 rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos,
1920                                                     pipe, len, flags);
1921         } else {
1922                 if (*ppos) {
1923                         rc = -ESPIPE;
1924                         goto out;
1925                 }
1926                 if (flags & SPLICE_F_NONBLOCK)
1927                         flags = MSG_DONTWAIT;
1928                 else
1929                         flags = 0;
1930                 rc = smc_rx_recvmsg(smc, NULL, pipe, len, flags);
1931         }
1932 out:
1933         release_sock(sk);
1934
1935         return rc;
1936 }
1937
1938 /* must look like tcp */
1939 static const struct proto_ops smc_sock_ops = {
1940         .family         = PF_SMC,
1941         .owner          = THIS_MODULE,
1942         .release        = smc_release,
1943         .bind           = smc_bind,
1944         .connect        = smc_connect,
1945         .socketpair     = sock_no_socketpair,
1946         .accept         = smc_accept,
1947         .getname        = smc_getname,
1948         .poll           = smc_poll,
1949         .ioctl          = smc_ioctl,
1950         .listen         = smc_listen,
1951         .shutdown       = smc_shutdown,
1952         .setsockopt     = smc_setsockopt,
1953         .getsockopt     = smc_getsockopt,
1954         .sendmsg        = smc_sendmsg,
1955         .recvmsg        = smc_recvmsg,
1956         .mmap           = sock_no_mmap,
1957         .sendpage       = smc_sendpage,
1958         .splice_read    = smc_splice_read,
1959 };
1960
1961 static int smc_create(struct net *net, struct socket *sock, int protocol,
1962                       int kern)
1963 {
1964         int family = (protocol == SMCPROTO_SMC6) ? PF_INET6 : PF_INET;
1965         struct smc_sock *smc;
1966         struct sock *sk;
1967         int rc;
1968
1969         rc = -ESOCKTNOSUPPORT;
1970         if (sock->type != SOCK_STREAM)
1971                 goto out;
1972
1973         rc = -EPROTONOSUPPORT;
1974         if (protocol != SMCPROTO_SMC && protocol != SMCPROTO_SMC6)
1975                 goto out;
1976
1977         rc = -ENOBUFS;
1978         sock->ops = &smc_sock_ops;
1979         sk = smc_sock_alloc(net, sock, protocol);
1980         if (!sk)
1981                 goto out;
1982
1983         /* create internal TCP socket for CLC handshake and fallback */
1984         smc = smc_sk(sk);
1985         smc->use_fallback = false; /* assume rdma capability first */
1986         smc->fallback_rsn = 0;
1987         rc = sock_create_kern(net, family, SOCK_STREAM, IPPROTO_TCP,
1988                               &smc->clcsock);
1989         if (rc) {
1990                 sk_common_release(sk);
1991                 goto out;
1992         }
1993         smc->sk.sk_sndbuf = max(smc->clcsock->sk->sk_sndbuf, SMC_BUF_MIN_SIZE);
1994         smc->sk.sk_rcvbuf = max(smc->clcsock->sk->sk_rcvbuf, SMC_BUF_MIN_SIZE);
1995
1996 out:
1997         return rc;
1998 }
1999
2000 static const struct net_proto_family smc_sock_family_ops = {
2001         .family = PF_SMC,
2002         .owner  = THIS_MODULE,
2003         .create = smc_create,
2004 };
2005
2006 unsigned int smc_net_id;
2007
2008 static __net_init int smc_net_init(struct net *net)
2009 {
2010         return smc_pnet_net_init(net);
2011 }
2012
2013 static void __net_exit smc_net_exit(struct net *net)
2014 {
2015         smc_pnet_net_exit(net);
2016 }
2017
2018 static struct pernet_operations smc_net_ops = {
2019         .init = smc_net_init,
2020         .exit = smc_net_exit,
2021         .id   = &smc_net_id,
2022         .size = sizeof(struct smc_net),
2023 };
2024
2025 static int __init smc_init(void)
2026 {
2027         int rc;
2028
2029         rc = register_pernet_subsys(&smc_net_ops);
2030         if (rc)
2031                 return rc;
2032
2033         rc = smc_pnet_init();
2034         if (rc)
2035                 goto out_pernet_subsys;
2036
2037         rc = smc_llc_init();
2038         if (rc) {
2039                 pr_err("%s: smc_llc_init fails with %d\n", __func__, rc);
2040                 goto out_pnet;
2041         }
2042
2043         rc = smc_cdc_init();
2044         if (rc) {
2045                 pr_err("%s: smc_cdc_init fails with %d\n", __func__, rc);
2046                 goto out_pnet;
2047         }
2048
2049         rc = proto_register(&smc_proto, 1);
2050         if (rc) {
2051                 pr_err("%s: proto_register(v4) fails with %d\n", __func__, rc);
2052                 goto out_pnet;
2053         }
2054
2055         rc = proto_register(&smc_proto6, 1);
2056         if (rc) {
2057                 pr_err("%s: proto_register(v6) fails with %d\n", __func__, rc);
2058                 goto out_proto;
2059         }
2060
2061         rc = sock_register(&smc_sock_family_ops);
2062         if (rc) {
2063                 pr_err("%s: sock_register fails with %d\n", __func__, rc);
2064                 goto out_proto6;
2065         }
2066         INIT_HLIST_HEAD(&smc_v4_hashinfo.ht);
2067         INIT_HLIST_HEAD(&smc_v6_hashinfo.ht);
2068
2069         rc = smc_ib_register_client();
2070         if (rc) {
2071                 pr_err("%s: ib_register fails with %d\n", __func__, rc);
2072                 goto out_sock;
2073         }
2074
2075         static_branch_enable(&tcp_have_smc);
2076         return 0;
2077
2078 out_sock:
2079         sock_unregister(PF_SMC);
2080 out_proto6:
2081         proto_unregister(&smc_proto6);
2082 out_proto:
2083         proto_unregister(&smc_proto);
2084 out_pnet:
2085         smc_pnet_exit();
2086 out_pernet_subsys:
2087         unregister_pernet_subsys(&smc_net_ops);
2088
2089         return rc;
2090 }
2091
2092 static void __exit smc_exit(void)
2093 {
2094         smc_core_exit();
2095         static_branch_disable(&tcp_have_smc);
2096         smc_ib_unregister_client();
2097         sock_unregister(PF_SMC);
2098         proto_unregister(&smc_proto6);
2099         proto_unregister(&smc_proto);
2100         smc_pnet_exit();
2101         unregister_pernet_subsys(&smc_net_ops);
2102 }
2103
2104 module_init(smc_init);
2105 module_exit(smc_exit);
2106
2107 MODULE_AUTHOR("Ursula Braun <ubraun@linux.vnet.ibm.com>");
2108 MODULE_DESCRIPTION("smc socket address family");
2109 MODULE_LICENSE("GPL");
2110 MODULE_ALIAS_NETPROTO(PF_SMC);