net/smc/af_smc.c

   1 /*
   2  *  Shared Memory Communications over RDMA (SMC-R) and RoCE
   3  *
   4  *  AF_SMC protocol family socket handler keeping the AF_INET sock address type
   5  *  applies to SOCK_STREAM sockets only
   6  *  offers an alternative communication option for TCP-protocol sockets
   7  *  applicable with RoCE-cards only
   8  *
   9  *  Initial restrictions:
  10  *    - support for alternate links postponed
  11  *
  12  *  Copyright IBM Corp. 2016, 2018
  13  *
  14  *  Author(s):  Ursula Braun <[email protected]>
  15  *              based on prototype from Frank Blaschka
  16  */
  17
  18 #define KMSG_COMPONENT "smc"
  19 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  20
  21 #include <linux/module.h>
  22 #include <linux/socket.h>
  23 #include <linux/workqueue.h>
  24 #include <linux/in.h>
  25 #include <linux/sched/signal.h>
  26 #include <linux/if_vlan.h>
  27
  28 #include <net/sock.h>
  29 #include <net/tcp.h>
  30 #include <net/smc.h>
  31 #include <asm/ioctls.h>
  32
  33 #include "smc.h"
  34 #include "smc_clc.h"
  35 #include "smc_llc.h"
  36 #include "smc_cdc.h"
  37 #include "smc_core.h"
  38 #include "smc_ib.h"
  39 #include "smc_ism.h"
  40 #include "smc_pnet.h"
  41 #include "smc_tx.h"
  42 #include "smc_rx.h"
  43 #include "smc_close.h"
  44
  45 static DEFINE_MUTEX(smc_create_lgr_pending);    /* serialize link group
  46                                                  * creation
  47                                                  */
  48
  49 static void smc_tcp_listen_work(struct work_struct *);
  50 static void smc_connect_work(struct work_struct *);
  51
  52 static void smc_set_keepalive(struct sock *sk, int val)
  53 {
  54         struct smc_sock *smc = smc_sk(sk);
  55
  56         smc->clcsock->sk->sk_prot->keepalive(smc->clcsock->sk, val);
  57 }
  58
  59 static struct smc_hashinfo smc_v4_hashinfo = {
  60         .lock = __RW_LOCK_UNLOCKED(smc_v4_hashinfo.lock),
  61 };
  62
  63 static struct smc_hashinfo smc_v6_hashinfo = {
  64         .lock = __RW_LOCK_UNLOCKED(smc_v6_hashinfo.lock),
  65 };
  66
  67 int smc_hash_sk(struct sock *sk)
  68 {
  69         struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
  70         struct hlist_head *head;
  71
  72         head = &h->ht;
  73
  74         write_lock_bh(&h->lock);
  75         sk_add_node(sk, head);
  76         sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
  77         write_unlock_bh(&h->lock);
  78
  79         return 0;
  80 }
  81 EXPORT_SYMBOL_GPL(smc_hash_sk);
  82
  83 void smc_unhash_sk(struct sock *sk)
  84 {
  85         struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
  86
  87         write_lock_bh(&h->lock);
  88         if (sk_del_node_init(sk))
  89                 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
  90         write_unlock_bh(&h->lock);
  91 }
  92 EXPORT_SYMBOL_GPL(smc_unhash_sk);
  93
  94 struct proto smc_proto = {
  95         .name           = "SMC",
  96         .owner          = THIS_MODULE,
  97         .keepalive      = smc_set_keepalive,
  98         .hash           = smc_hash_sk,
  99         .unhash         = smc_unhash_sk,
 100         .obj_size       = sizeof(struct smc_sock),
 101         .h.smc_hash     = &smc_v4_hashinfo,
 102         .slab_flags     = SLAB_TYPESAFE_BY_RCU,
 103 };
 104 EXPORT_SYMBOL_GPL(smc_proto);
 105
 106 struct proto smc_proto6 = {
 107         .name           = "SMC6",
 108         .owner          = THIS_MODULE,
 109         .keepalive      = smc_set_keepalive,
 110         .hash           = smc_hash_sk,
 111         .unhash         = smc_unhash_sk,
 112         .obj_size       = sizeof(struct smc_sock),
 113         .h.smc_hash     = &smc_v6_hashinfo,
 114         .slab_flags     = SLAB_TYPESAFE_BY_RCU,
 115 };
 116 EXPORT_SYMBOL_GPL(smc_proto6);
 117
 118 static int smc_release(struct socket *sock)
 119 {
 120         struct sock *sk = sock->sk;
 121         struct smc_sock *smc;
 122         int rc = 0;
 123
 124         if (!sk)
 125                 goto out;
 126
 127         smc = smc_sk(sk);
 128
 129         /* cleanup for a dangling non-blocking connect */
 130         flush_work(&smc->connect_work);
 131         kfree(smc->connect_info);
 132         smc->connect_info = NULL;
 133
 134         if (sk->sk_state == SMC_LISTEN)
 135                 /* smc_close_non_accepted() is called and acquires
 136                  * sock lock for child sockets again
 137                  */
 138                 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 139         else
 140                 lock_sock(sk);
 141
 142         if (!smc->use_fallback) {
 143                 rc = smc_close_active(smc);
 144                 sock_set_flag(sk, SOCK_DEAD);
 145                 sk->sk_shutdown |= SHUTDOWN_MASK;
 146         }
 147         if (smc->clcsock) {
 148                 sock_release(smc->clcsock);
 149                 smc->clcsock = NULL;
 150         }
 151         if (smc->use_fallback) {
 152                 if (sk->sk_state != SMC_LISTEN && sk->sk_state != SMC_INIT)
 153                         sock_put(sk); /* passive closing */
 154                 sk->sk_state = SMC_CLOSED;
 155                 sk->sk_state_change(sk);
 156         }
 157
 158         /* detach socket */
 159         sock_orphan(sk);
 160         sock->sk = NULL;
 161         if (!smc->use_fallback && sk->sk_state == SMC_CLOSED)
 162                 smc_conn_free(&smc->conn);
 163         release_sock(sk);
 164
 165         sk->sk_prot->unhash(sk);
 166         sock_put(sk); /* final sock_put */
 167 out:
 168         return rc;
 169 }
 170
 171 static void smc_destruct(struct sock *sk)
 172 {
 173         if (sk->sk_state != SMC_CLOSED)
 174                 return;
 175         if (!sock_flag(sk, SOCK_DEAD))
 176                 return;
 177
 178         sk_refcnt_debug_dec(sk);
 179 }
 180
 181 static struct sock *smc_sock_alloc(struct net *net, struct socket *sock,
 182                                    int protocol)
 183 {
 184         struct smc_sock *smc;
 185         struct proto *prot;
 186         struct sock *sk;
 187
 188         prot = (protocol == SMCPROTO_SMC6) ? &smc_proto6 : &smc_proto;
 189         sk = sk_alloc(net, PF_SMC, GFP_KERNEL, prot, 0);
 190         if (!sk)
 191                 return NULL;
 192
 193         sock_init_data(sock, sk); /* sets sk_refcnt to 1 */
 194         sk->sk_state = SMC_INIT;
 195         sk->sk_destruct = smc_destruct;
 196         sk->sk_protocol = protocol;
 197         smc = smc_sk(sk);
 198         INIT_WORK(&smc->tcp_listen_work, smc_tcp_listen_work);
 199         INIT_WORK(&smc->connect_work, smc_connect_work);
 200         INIT_DELAYED_WORK(&smc->conn.tx_work, smc_tx_work);
 201         INIT_LIST_HEAD(&smc->accept_q);
 202         spin_lock_init(&smc->accept_q_lock);
 203         spin_lock_init(&smc->conn.send_lock);
 204         sk->sk_prot->hash(sk);
 205         sk_refcnt_debug_inc(sk);
 206
 207         return sk;
 208 }
 209
 210 static int smc_bind(struct socket *sock, struct sockaddr *uaddr,
 211                     int addr_len)
 212 {
 213         struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
 214         struct sock *sk = sock->sk;
 215         struct smc_sock *smc;
 216         int rc;
 217
 218         smc = smc_sk(sk);
 219
 220         /* replicate tests from inet_bind(), to be safe wrt. future changes */
 221         rc = -EINVAL;
 222         if (addr_len < sizeof(struct sockaddr_in))
 223                 goto out;
 224
 225         rc = -EAFNOSUPPORT;
 226         if (addr->sin_family != AF_INET &&
 227             addr->sin_family != AF_INET6 &&
 228             addr->sin_family != AF_UNSPEC)
 229                 goto out;
 230         /* accept AF_UNSPEC (mapped to AF_INET) only if s_addr is INADDR_ANY */
 231         if (addr->sin_family == AF_UNSPEC &&
 232             addr->sin_addr.s_addr != htonl(INADDR_ANY))
 233                 goto out;
 234
 235         lock_sock(sk);
 236
 237         /* Check if socket is already active */
 238         rc = -EINVAL;
 239         if (sk->sk_state != SMC_INIT)
 240                 goto out_rel;
 241
 242         smc->clcsock->sk->sk_reuse = sk->sk_reuse;
 243         rc = kernel_bind(smc->clcsock, uaddr, addr_len);
 244
 245 out_rel:
 246         release_sock(sk);
 247 out:
 248         return rc;
 249 }
 250
 251 static void smc_copy_sock_settings(struct sock *nsk, struct sock *osk,
 252                                    unsigned long mask)
 253 {
 254         /* options we don't get control via setsockopt for */
 255         nsk->sk_type = osk->sk_type;
 256         nsk->sk_sndbuf = osk->sk_sndbuf;
 257         nsk->sk_rcvbuf = osk->sk_rcvbuf;
 258         nsk->sk_sndtimeo = osk->sk_sndtimeo;
 259         nsk->sk_rcvtimeo = osk->sk_rcvtimeo;
 260         nsk->sk_mark = osk->sk_mark;
 261         nsk->sk_priority = osk->sk_priority;
 262         nsk->sk_rcvlowat = osk->sk_rcvlowat;
 263         nsk->sk_bound_dev_if = osk->sk_bound_dev_if;
 264         nsk->sk_err = osk->sk_err;
 265
 266         nsk->sk_flags &= ~mask;
 267         nsk->sk_flags |= osk->sk_flags & mask;
 268 }
 269
 270 #define SK_FLAGS_SMC_TO_CLC ((1UL << SOCK_URGINLINE) | \
 271                              (1UL << SOCK_KEEPOPEN) | \
 272                              (1UL << SOCK_LINGER) | \
 273                              (1UL << SOCK_BROADCAST) | \
 274                              (1UL << SOCK_TIMESTAMP) | \
 275                              (1UL << SOCK_DBG) | \
 276                              (1UL << SOCK_RCVTSTAMP) | \
 277                              (1UL << SOCK_RCVTSTAMPNS) | \
 278                              (1UL << SOCK_LOCALROUTE) | \
 279                              (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
 280                              (1UL << SOCK_RXQ_OVFL) | \
 281                              (1UL << SOCK_WIFI_STATUS) | \
 282                              (1UL << SOCK_NOFCS) | \
 283                              (1UL << SOCK_FILTER_LOCKED))
 284 /* copy only relevant settings and flags of SOL_SOCKET level from smc to
 285  * clc socket (since smc is not called for these options from net/core)
 286  */
 287 static void smc_copy_sock_settings_to_clc(struct smc_sock *smc)
 288 {
 289         smc_copy_sock_settings(smc->clcsock->sk, &smc->sk, SK_FLAGS_SMC_TO_CLC);
 290 }
 291
 292 #define SK_FLAGS_CLC_TO_SMC ((1UL << SOCK_URGINLINE) | \
 293                              (1UL << SOCK_KEEPOPEN) | \
 294                              (1UL << SOCK_LINGER) | \
 295                              (1UL << SOCK_DBG))
 296 /* copy only settings and flags relevant for smc from clc to smc socket */
 297 static void smc_copy_sock_settings_to_smc(struct smc_sock *smc)
 298 {
 299         smc_copy_sock_settings(&smc->sk, smc->clcsock->sk, SK_FLAGS_CLC_TO_SMC);
 300 }
 301
 302 /* register a new rmb, optionally send confirm_rkey msg to register with peer */
 303 static int smc_reg_rmb(struct smc_link *link, struct smc_buf_desc *rmb_desc,
 304                        bool conf_rkey)
 305 {
 306         /* register memory region for new rmb */
 307         if (smc_wr_reg_send(link, rmb_desc->mr_rx[SMC_SINGLE_LINK])) {
 308                 rmb_desc->regerr = 1;
 309                 return -EFAULT;
 310         }
 311         if (!conf_rkey)
 312                 return 0;
 313         /* exchange confirm_rkey msg with peer */
 314         if (smc_llc_do_confirm_rkey(link, rmb_desc)) {
 315                 rmb_desc->regerr = 1;
 316                 return -EFAULT;
 317         }
 318         return 0;
 319 }
 320
 321 static int smc_clnt_conf_first_link(struct smc_sock *smc)
 322 {
 323         struct net *net = sock_net(smc->clcsock->sk);
 324         struct smc_link_group *lgr = smc->conn.lgr;
 325         struct smc_link *link;
 326         int rest;
 327         int rc;
 328
 329         link = &lgr->lnk[SMC_SINGLE_LINK];
 330         /* receive CONFIRM LINK request from server over RoCE fabric */
 331         rest = wait_for_completion_interruptible_timeout(
 332                 &link->llc_confirm,
 333                 SMC_LLC_WAIT_FIRST_TIME);
 334         if (rest <= 0) {
 335                 struct smc_clc_msg_decline dclc;
 336
 337                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
 338                                       SMC_CLC_DECLINE);
 339                 return rc;
 340         }
 341
 342         if (link->llc_confirm_rc)
 343                 return SMC_CLC_DECL_RMBE_EC;
 344
 345         rc = smc_ib_modify_qp_rts(link);
 346         if (rc)
 347                 return SMC_CLC_DECL_ERR_RDYLNK;
 348
 349         smc_wr_remember_qp_attr(link);
 350
 351         if (smc_reg_rmb(link, smc->conn.rmb_desc, false))
 352                 return SMC_CLC_DECL_ERR_REGRMB;
 353
 354         /* send CONFIRM LINK response over RoCE fabric */
 355         rc = smc_llc_send_confirm_link(link, SMC_LLC_RESP);
 356         if (rc < 0)
 357                 return SMC_CLC_DECL_TIMEOUT_CL;
 358
 359         /* receive ADD LINK request from server over RoCE fabric */
 360         rest = wait_for_completion_interruptible_timeout(&link->llc_add,
 361                                                          SMC_LLC_WAIT_TIME);
 362         if (rest <= 0) {
 363                 struct smc_clc_msg_decline dclc;
 364
 365                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
 366                                       SMC_CLC_DECLINE);
 367                 return rc;
 368         }
 369
 370         /* send add link reject message, only one link supported for now */
 371         rc = smc_llc_send_add_link(link,
 372                                    link->smcibdev->mac[link->ibport - 1],
 373                                    link->gid, SMC_LLC_RESP);
 374         if (rc < 0)
 375                 return SMC_CLC_DECL_TIMEOUT_AL;
 376
 377         smc_llc_link_active(link, net->ipv4.sysctl_tcp_keepalive_time);
 378
 379         return 0;
 380 }
 381
 382 static void smcr_conn_save_peer_info(struct smc_sock *smc,
 383                                      struct smc_clc_msg_accept_confirm *clc)
 384 {
 385         int bufsize = smc_uncompress_bufsize(clc->rmbe_size);
 386
 387         smc->conn.peer_rmbe_idx = clc->rmbe_idx;
 388         smc->conn.local_tx_ctrl.token = ntohl(clc->rmbe_alert_token);
 389         smc->conn.peer_rmbe_size = bufsize;
 390         atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
 391         smc->conn.tx_off = bufsize * (smc->conn.peer_rmbe_idx - 1);
 392 }
 393
 394 static void smcd_conn_save_peer_info(struct smc_sock *smc,
 395                                      struct smc_clc_msg_accept_confirm *clc)
 396 {
 397         int bufsize = smc_uncompress_bufsize(clc->dmbe_size);
 398
 399         smc->conn.peer_rmbe_idx = clc->dmbe_idx;
 400         smc->conn.peer_token = clc->token;
 401         /* msg header takes up space in the buffer */
 402         smc->conn.peer_rmbe_size = bufsize - sizeof(struct smcd_cdc_msg);
 403         atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
 404         smc->conn.tx_off = bufsize * smc->conn.peer_rmbe_idx;
 405 }
 406
 407 static void smc_conn_save_peer_info(struct smc_sock *smc,
 408                                     struct smc_clc_msg_accept_confirm *clc)
 409 {
 410         if (smc->conn.lgr->is_smcd)
 411                 smcd_conn_save_peer_info(smc, clc);
 412         else
 413                 smcr_conn_save_peer_info(smc, clc);
 414 }
 415
 416 static void smc_link_save_peer_info(struct smc_link *link,
 417                                     struct smc_clc_msg_accept_confirm *clc)
 418 {
 419         link->peer_qpn = ntoh24(clc->qpn);
 420         memcpy(link->peer_gid, clc->lcl.gid, SMC_GID_SIZE);
 421         memcpy(link->peer_mac, clc->lcl.mac, sizeof(link->peer_mac));
 422         link->peer_psn = ntoh24(clc->psn);
 423         link->peer_mtu = clc->qp_mtu;
 424 }
 425
 426 /* fall back during connect */
 427 static int smc_connect_fallback(struct smc_sock *smc, int reason_code)
 428 {
 429         smc->use_fallback = true;
 430         smc->fallback_rsn = reason_code;
 431         smc_copy_sock_settings_to_clc(smc);
 432         if (smc->sk.sk_state == SMC_INIT)
 433                 smc->sk.sk_state = SMC_ACTIVE;
 434         return 0;
 435 }
 436
 437 /* decline and fall back during connect */
 438 static int smc_connect_decline_fallback(struct smc_sock *smc, int reason_code)
 439 {
 440         int rc;
 441
 442         if (reason_code < 0) { /* error, fallback is not possible */
 443                 if (smc->sk.sk_state == SMC_INIT)
 444                         sock_put(&smc->sk); /* passive closing */
 445                 return reason_code;
 446         }
 447         if (reason_code != SMC_CLC_DECL_PEERDECL) {
 448                 rc = smc_clc_send_decline(smc, reason_code);
 449                 if (rc < 0) {
 450                         if (smc->sk.sk_state == SMC_INIT)
 451                                 sock_put(&smc->sk); /* passive closing */
 452                         return rc;
 453                 }
 454         }
 455         return smc_connect_fallback(smc, reason_code);
 456 }
 457
 458 /* abort connecting */
 459 static int smc_connect_abort(struct smc_sock *smc, int reason_code,
 460                              int local_contact)
 461 {
 462         if (local_contact == SMC_FIRST_CONTACT)
 463                 smc_lgr_forget(smc->conn.lgr);
 464         mutex_unlock(&smc_create_lgr_pending);
 465         smc_conn_free(&smc->conn);
 466         return reason_code;
 467 }
 468
 469 /* check if there is a rdma device available for this connection. */
 470 /* called for connect and listen */
 471 static int smc_check_rdma(struct smc_sock *smc, struct smc_ib_device **ibdev,
 472                           u8 *ibport, unsigned short vlan_id, u8 gid[])
 473 {
 474         int reason_code = 0;
 475
 476         /* PNET table look up: search active ib_device and port
 477          * within same PNETID that also contains the ethernet device
 478          * used for the internal TCP socket
 479          */
 480         smc_pnet_find_roce_resource(smc->clcsock->sk, ibdev, ibport, vlan_id,
 481                                     gid);
 482         if (!(*ibdev))
 483                 reason_code = SMC_CLC_DECL_CNFERR; /* configuration error */
 484
 485         return reason_code;
 486 }
 487
 488 /* check if there is an ISM device available for this connection. */
 489 /* called for connect and listen */
 490 static int smc_check_ism(struct smc_sock *smc, struct smcd_dev **ismdev)
 491 {
 492         /* Find ISM device with same PNETID as connecting interface  */
 493         smc_pnet_find_ism_resource(smc->clcsock->sk, ismdev);
 494         if (!(*ismdev))
 495                 return SMC_CLC_DECL_CNFERR; /* configuration error */
 496         return 0;
 497 }
 498
 499 /* Check for VLAN ID and register it on ISM device just for CLC handshake */
 500 static int smc_connect_ism_vlan_setup(struct smc_sock *smc,
 501                                       struct smcd_dev *ismdev,
 502                                       unsigned short vlan_id)
 503 {
 504         if (vlan_id && smc_ism_get_vlan(ismdev, vlan_id))
 505                 return SMC_CLC_DECL_CNFERR;
 506         return 0;
 507 }
 508
 509 /* cleanup temporary VLAN ID registration used for CLC handshake. If ISM is
 510  * used, the VLAN ID will be registered again during the connection setup.
 511  */
 512 static int smc_connect_ism_vlan_cleanup(struct smc_sock *smc, bool is_smcd,
 513                                         struct smcd_dev *ismdev,
 514                                         unsigned short vlan_id)
 515 {
 516         if (!is_smcd)
 517                 return 0;
 518         if (vlan_id && smc_ism_put_vlan(ismdev, vlan_id))
 519                 return SMC_CLC_DECL_CNFERR;
 520         return 0;
 521 }
 522
 523 /* CLC handshake during connect */
 524 static int smc_connect_clc(struct smc_sock *smc, int smc_type,
 525                            struct smc_clc_msg_accept_confirm *aclc,
 526                            struct smc_ib_device *ibdev, u8 ibport,
 527                            u8 gid[], struct smcd_dev *ismdev)
 528 {
 529         int rc = 0;
 530
 531         /* do inband token exchange */
 532         rc = smc_clc_send_proposal(smc, smc_type, ibdev, ibport, gid, ismdev);
 533         if (rc)
 534                 return rc;
 535         /* receive SMC Accept CLC message */
 536         return smc_clc_wait_msg(smc, aclc, sizeof(*aclc), SMC_CLC_ACCEPT);
 537 }
 538
 539 /* setup for RDMA connection of client */
 540 static int smc_connect_rdma(struct smc_sock *smc,
 541                             struct smc_clc_msg_accept_confirm *aclc,
 542                             struct smc_ib_device *ibdev, u8 ibport)
 543 {
 544         int local_contact = SMC_FIRST_CONTACT;
 545         struct smc_link *link;
 546         int reason_code = 0;
 547
 548         mutex_lock(&smc_create_lgr_pending);
 549         local_contact = smc_conn_create(smc, false, aclc->hdr.flag, ibdev,
 550                                         ibport, &aclc->lcl, NULL, 0);
 551         if (local_contact < 0) {
 552                 if (local_contact == -ENOMEM)
 553                         reason_code = SMC_CLC_DECL_MEM;/* insufficient memory*/
 554                 else if (local_contact == -ENOLINK)
 555                         reason_code = SMC_CLC_DECL_SYNCERR; /* synchr. error */
 556                 else
 557                         reason_code = SMC_CLC_DECL_INTERR; /* other error */
 558                 return smc_connect_abort(smc, reason_code, 0);
 559         }
 560         link = &smc->conn.lgr->lnk[SMC_SINGLE_LINK];
 561
 562         smc_conn_save_peer_info(smc, aclc);
 563
 564         /* create send buffer and rmb */
 565         if (smc_buf_create(smc, false))
 566                 return smc_connect_abort(smc, SMC_CLC_DECL_MEM, local_contact);
 567
 568         if (local_contact == SMC_FIRST_CONTACT)
 569                 smc_link_save_peer_info(link, aclc);
 570
 571         if (smc_rmb_rtoken_handling(&smc->conn, aclc))
 572                 return smc_connect_abort(smc, SMC_CLC_DECL_ERR_RTOK,
 573                                          local_contact);
 574
 575         smc_close_init(smc);
 576         smc_rx_init(smc);
 577
 578         if (local_contact == SMC_FIRST_CONTACT) {
 579                 if (smc_ib_ready_link(link))
 580                         return smc_connect_abort(smc, SMC_CLC_DECL_ERR_RDYLNK,
 581                                                  local_contact);
 582         } else {
 583                 if (!smc->conn.rmb_desc->reused &&
 584                     smc_reg_rmb(link, smc->conn.rmb_desc, true))
 585                         return smc_connect_abort(smc, SMC_CLC_DECL_ERR_REGRMB,
 586                                                  local_contact);
 587         }
 588         smc_rmb_sync_sg_for_device(&smc->conn);
 589
 590         reason_code = smc_clc_send_confirm(smc);
 591         if (reason_code)
 592                 return smc_connect_abort(smc, reason_code, local_contact);
 593
 594         smc_tx_init(smc);
 595
 596         if (local_contact == SMC_FIRST_CONTACT) {
 597                 /* QP confirmation over RoCE fabric */
 598                 reason_code = smc_clnt_conf_first_link(smc);
 599                 if (reason_code)
 600                         return smc_connect_abort(smc, reason_code,
 601                                                  local_contact);
 602         }
 603         mutex_unlock(&smc_create_lgr_pending);
 604
 605         smc_copy_sock_settings_to_clc(smc);
 606         if (smc->sk.sk_state == SMC_INIT)
 607                 smc->sk.sk_state = SMC_ACTIVE;
 608
 609         return 0;
 610 }
 611
 612 /* setup for ISM connection of client */
 613 static int smc_connect_ism(struct smc_sock *smc,
 614                            struct smc_clc_msg_accept_confirm *aclc,
 615                            struct smcd_dev *ismdev)
 616 {
 617         int local_contact = SMC_FIRST_CONTACT;
 618         int rc = 0;
 619
 620         mutex_lock(&smc_create_lgr_pending);
 621         local_contact = smc_conn_create(smc, true, aclc->hdr.flag, NULL, 0,
 622                                         NULL, ismdev, aclc->gid);
 623         if (local_contact < 0)
 624                 return smc_connect_abort(smc, SMC_CLC_DECL_MEM, 0);
 625
 626         /* Create send and receive buffers */
 627         if (smc_buf_create(smc, true))
 628                 return smc_connect_abort(smc, SMC_CLC_DECL_MEM, local_contact);
 629
 630         smc_conn_save_peer_info(smc, aclc);
 631         smc_close_init(smc);
 632         smc_rx_init(smc);
 633         smc_tx_init(smc);
 634
 635         rc = smc_clc_send_confirm(smc);
 636         if (rc)
 637                 return smc_connect_abort(smc, rc, local_contact);
 638         mutex_unlock(&smc_create_lgr_pending);
 639
 640         smc_copy_sock_settings_to_clc(smc);
 641         if (smc->sk.sk_state == SMC_INIT)
 642                 smc->sk.sk_state = SMC_ACTIVE;
 643
 644         return 0;
 645 }
 646
 647 /* perform steps before actually connecting */
 648 static int __smc_connect(struct smc_sock *smc)
 649 {
 650         bool ism_supported = false, rdma_supported = false;
 651         struct smc_clc_msg_accept_confirm aclc;
 652         struct smc_ib_device *ibdev;
 653         struct smcd_dev *ismdev;
 654         u8 gid[SMC_GID_SIZE];
 655         unsigned short vlan;
 656         int smc_type;
 657         int rc = 0;
 658         u8 ibport;
 659
 660         sock_hold(&smc->sk); /* sock put in passive closing */
 661
 662         if (smc->use_fallback)
 663                 return smc_connect_fallback(smc, smc->fallback_rsn);
 664
 665         /* if peer has not signalled SMC-capability, fall back */
 666         if (!tcp_sk(smc->clcsock->sk)->syn_smc)
 667                 return smc_connect_fallback(smc, SMC_CLC_DECL_PEERNOSMC);
 668
 669         /* IPSec connections opt out of SMC-R optimizations */
 670         if (using_ipsec(smc))
 671                 return smc_connect_decline_fallback(smc, SMC_CLC_DECL_IPSEC);
 672
 673         /* check for VLAN ID */
 674         if (smc_vlan_by_tcpsk(smc->clcsock, &vlan))
 675                 return smc_connect_decline_fallback(smc, SMC_CLC_DECL_CNFERR);
 676
 677         /* check if there is an ism device available */
 678         if (!smc_check_ism(smc, &ismdev) &&
 679             !smc_connect_ism_vlan_setup(smc, ismdev, vlan)) {
 680                 /* ISM is supported for this connection */
 681                 ism_supported = true;
 682                 smc_type = SMC_TYPE_D;
 683         }
 684
 685         /* check if there is a rdma device available */
 686         if (!smc_check_rdma(smc, &ibdev, &ibport, vlan, gid)) {
 687                 /* RDMA is supported for this connection */
 688                 rdma_supported = true;
 689                 if (ism_supported)
 690                         smc_type = SMC_TYPE_B; /* both */
 691                 else
 692                         smc_type = SMC_TYPE_R; /* only RDMA */
 693         }
 694
 695         /* if neither ISM nor RDMA are supported, fallback */
 696         if (!rdma_supported && !ism_supported)
 697                 return smc_connect_decline_fallback(smc, SMC_CLC_DECL_NOSMCDEV);
 698
 699         /* perform CLC handshake */
 700         rc = smc_connect_clc(smc, smc_type, &aclc, ibdev, ibport, gid, ismdev);
 701         if (rc) {
 702                 smc_connect_ism_vlan_cleanup(smc, ism_supported, ismdev, vlan);
 703                 return smc_connect_decline_fallback(smc, rc);
 704         }
 705
 706         /* depending on previous steps, connect using rdma or ism */
 707         if (rdma_supported && aclc.hdr.path == SMC_TYPE_R)
 708                 rc = smc_connect_rdma(smc, &aclc, ibdev, ibport);
 709         else if (ism_supported && aclc.hdr.path == SMC_TYPE_D)
 710                 rc = smc_connect_ism(smc, &aclc, ismdev);
 711         else
 712                 rc = SMC_CLC_DECL_MODEUNSUPP;
 713         if (rc) {
 714                 smc_connect_ism_vlan_cleanup(smc, ism_supported, ismdev, vlan);
 715                 return smc_connect_decline_fallback(smc, rc);
 716         }
 717
 718         smc_connect_ism_vlan_cleanup(smc, ism_supported, ismdev, vlan);
 719         return 0;
 720 }
 721
 722 static void smc_connect_work(struct work_struct *work)
 723 {
 724         struct smc_sock *smc = container_of(work, struct smc_sock,
 725                                             connect_work);
 726         int rc;
 727
 728         lock_sock(&smc->sk);
 729         rc = kernel_connect(smc->clcsock, &smc->connect_info->addr,
 730                             smc->connect_info->alen, smc->connect_info->flags);
 731         if (smc->clcsock->sk->sk_err) {
 732                 smc->sk.sk_err = smc->clcsock->sk->sk_err;
 733                 goto out;
 734         }
 735         if (rc < 0) {
 736                 smc->sk.sk_err = -rc;
 737                 goto out;
 738         }
 739
 740         rc = __smc_connect(smc);
 741         if (rc < 0)
 742                 smc->sk.sk_err = -rc;
 743
 744 out:
 745         if (smc->sk.sk_err)
 746                 smc->sk.sk_state_change(&smc->sk);
 747         else
 748                 smc->sk.sk_write_space(&smc->sk);
 749         kfree(smc->connect_info);
 750         smc->connect_info = NULL;
 751         release_sock(&smc->sk);
 752 }
 753
 754 static int smc_connect(struct socket *sock, struct sockaddr *addr,
 755                        int alen, int flags)
 756 {
 757         struct sock *sk = sock->sk;
 758         struct smc_sock *smc;
 759         int rc = -EINVAL;
 760
 761         smc = smc_sk(sk);
 762
 763         /* separate smc parameter checking to be safe */
 764         if (alen < sizeof(addr->sa_family))
 765                 goto out_err;
 766         if (addr->sa_family != AF_INET && addr->sa_family != AF_INET6)
 767                 goto out_err;
 768
 769         lock_sock(sk);
 770         switch (sk->sk_state) {
 771         default:
 772                 goto out;
 773         case SMC_ACTIVE:
 774                 rc = -EISCONN;
 775                 goto out;
 776         case SMC_INIT:
 777                 rc = 0;
 778                 break;
 779         }
 780
 781         smc_copy_sock_settings_to_clc(smc);
 782         tcp_sk(smc->clcsock->sk)->syn_smc = 1;
 783         if (flags & O_NONBLOCK) {
 784                 if (smc->connect_info) {
 785                         rc = -EALREADY;
 786                         goto out;
 787                 }
 788                 smc->connect_info = kzalloc(alen + 2 * sizeof(int), GFP_KERNEL);
 789                 if (!smc->connect_info) {
 790                         rc = -ENOMEM;
 791                         goto out;
 792                 }
 793                 smc->connect_info->alen = alen;
 794                 smc->connect_info->flags = flags ^ O_NONBLOCK;
 795                 memcpy(&smc->connect_info->addr, addr, alen);
 796                 schedule_work(&smc->connect_work);
 797                 rc = -EINPROGRESS;
 798         } else {
 799                 rc = kernel_connect(smc->clcsock, addr, alen, flags);
 800                 if (rc)
 801                         goto out;
 802
 803                 rc = __smc_connect(smc);
 804                 if (rc < 0)
 805                         goto out;
 806                 else
 807                         rc = 0; /* success cases including fallback */
 808         }
 809
 810 out:
 811         release_sock(sk);
 812 out_err:
 813         return rc;
 814 }
 815
 816 static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc)
 817 {
 818         struct socket *new_clcsock = NULL;
 819         struct sock *lsk = &lsmc->sk;
 820         struct sock *new_sk;
 821         int rc;
 822
 823         release_sock(lsk);
 824         new_sk = smc_sock_alloc(sock_net(lsk), NULL, lsk->sk_protocol);
 825         if (!new_sk) {
 826                 rc = -ENOMEM;
 827                 lsk->sk_err = ENOMEM;
 828                 *new_smc = NULL;
 829                 lock_sock(lsk);
 830                 goto out;
 831         }
 832         *new_smc = smc_sk(new_sk);
 833
 834         rc = kernel_accept(lsmc->clcsock, &new_clcsock, 0);
 835         lock_sock(lsk);
 836         if  (rc < 0)
 837                 lsk->sk_err = -rc;
 838         if (rc < 0 || lsk->sk_state == SMC_CLOSED) {
 839                 if (new_clcsock)
 840                         sock_release(new_clcsock);
 841                 new_sk->sk_state = SMC_CLOSED;
 842                 sock_set_flag(new_sk, SOCK_DEAD);
 843                 new_sk->sk_prot->unhash(new_sk);
 844                 sock_put(new_sk); /* final */
 845                 *new_smc = NULL;
 846                 goto out;
 847         }
 848
 849         (*new_smc)->clcsock = new_clcsock;
 850 out:
 851         return rc;
 852 }
 853
 854 /* add a just created sock to the accept queue of the listen sock as
 855  * candidate for a following socket accept call from user space
 856  */
 857 static void smc_accept_enqueue(struct sock *parent, struct sock *sk)
 858 {
 859         struct smc_sock *par = smc_sk(parent);
 860
 861         sock_hold(sk); /* sock_put in smc_accept_unlink () */
 862         spin_lock(&par->accept_q_lock);
 863         list_add_tail(&smc_sk(sk)->accept_q, &par->accept_q);
 864         spin_unlock(&par->accept_q_lock);
 865         sk_acceptq_added(parent);
 866 }
 867
 868 /* remove a socket from the accept queue of its parental listening socket */
 869 static void smc_accept_unlink(struct sock *sk)
 870 {
 871         struct smc_sock *par = smc_sk(sk)->listen_smc;
 872
 873         spin_lock(&par->accept_q_lock);
 874         list_del_init(&smc_sk(sk)->accept_q);
 875         spin_unlock(&par->accept_q_lock);
 876         sk_acceptq_removed(&smc_sk(sk)->listen_smc->sk);
 877         sock_put(sk); /* sock_hold in smc_accept_enqueue */
 878 }
 879
 880 /* remove a sock from the accept queue to bind it to a new socket created
 881  * for a socket accept call from user space
 882  */
 883 struct sock *smc_accept_dequeue(struct sock *parent,
 884                                 struct socket *new_sock)
 885 {
 886         struct smc_sock *isk, *n;
 887         struct sock *new_sk;
 888
 889         list_for_each_entry_safe(isk, n, &smc_sk(parent)->accept_q, accept_q) {
 890                 new_sk = (struct sock *)isk;
 891
 892                 smc_accept_unlink(new_sk);
 893                 if (new_sk->sk_state == SMC_CLOSED) {
 894                         if (isk->clcsock) {
 895                                 sock_release(isk->clcsock);
 896                                 isk->clcsock = NULL;
 897                         }
 898                         new_sk->sk_prot->unhash(new_sk);
 899                         sock_put(new_sk); /* final */
 900                         continue;
 901                 }
 902                 if (new_sock)
 903                         sock_graft(new_sk, new_sock);
 904                 return new_sk;
 905         }
 906         return NULL;
 907 }
 908
 909 /* clean up for a created but never accepted sock */
 910 void smc_close_non_accepted(struct sock *sk)
 911 {
 912         struct smc_sock *smc = smc_sk(sk);
 913
 914         lock_sock(sk);
 915         if (!sk->sk_lingertime)
 916                 /* wait for peer closing */
 917                 sk->sk_lingertime = SMC_MAX_STREAM_WAIT_TIMEOUT;
 918         if (!smc->use_fallback) {
 919                 smc_close_active(smc);
 920                 sock_set_flag(sk, SOCK_DEAD);
 921                 sk->sk_shutdown |= SHUTDOWN_MASK;
 922         }
 923         if (smc->clcsock) {
 924                 struct socket *tcp;
 925
 926                 tcp = smc->clcsock;
 927                 smc->clcsock = NULL;
 928                 sock_release(tcp);
 929         }
 930         if (smc->use_fallback) {
 931                 sock_put(sk); /* passive closing */
 932                 sk->sk_state = SMC_CLOSED;
 933         } else {
 934                 if (sk->sk_state == SMC_CLOSED)
 935                         smc_conn_free(&smc->conn);
 936         }
 937         release_sock(sk);
 938         sk->sk_prot->unhash(sk);
 939         sock_put(sk); /* final sock_put */
 940 }
 941
 942 static int smc_serv_conf_first_link(struct smc_sock *smc)
 943 {
 944         struct net *net = sock_net(smc->clcsock->sk);
 945         struct smc_link_group *lgr = smc->conn.lgr;
 946         struct smc_link *link;
 947         int rest;
 948         int rc;
 949
 950         link = &lgr->lnk[SMC_SINGLE_LINK];
 951
 952         if (smc_reg_rmb(link, smc->conn.rmb_desc, false))
 953                 return SMC_CLC_DECL_ERR_REGRMB;
 954
 955         /* send CONFIRM LINK request to client over the RoCE fabric */
 956         rc = smc_llc_send_confirm_link(link, SMC_LLC_REQ);
 957         if (rc < 0)
 958                 return SMC_CLC_DECL_TIMEOUT_CL;
 959
 960         /* receive CONFIRM LINK response from client over the RoCE fabric */
 961         rest = wait_for_completion_interruptible_timeout(
 962                 &link->llc_confirm_resp,
 963                 SMC_LLC_WAIT_FIRST_TIME);
 964         if (rest <= 0) {
 965                 struct smc_clc_msg_decline dclc;
 966
 967                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
 968                                       SMC_CLC_DECLINE);
 969                 return rc;
 970         }
 971
 972         if (link->llc_confirm_resp_rc)
 973                 return SMC_CLC_DECL_RMBE_EC;
 974
 975         /* send ADD LINK request to client over the RoCE fabric */
 976         rc = smc_llc_send_add_link(link,
 977                                    link->smcibdev->mac[link->ibport - 1],
 978                                    link->gid, SMC_LLC_REQ);
 979         if (rc < 0)
 980                 return SMC_CLC_DECL_TIMEOUT_AL;
 981
 982         /* receive ADD LINK response from client over the RoCE fabric */
 983         rest = wait_for_completion_interruptible_timeout(&link->llc_add_resp,
 984                                                          SMC_LLC_WAIT_TIME);
 985         if (rest <= 0) {
 986                 struct smc_clc_msg_decline dclc;
 987
 988                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
 989                                       SMC_CLC_DECLINE);
 990                 return rc;
 991         }
 992
 993         smc_llc_link_active(link, net->ipv4.sysctl_tcp_keepalive_time);
 994
 995         return 0;
 996 }
 997
 998 /* listen worker: finish */
 999 static void smc_listen_out(struct smc_sock *new_smc)
1000 {
1001         struct smc_sock *lsmc = new_smc->listen_smc;
1002         struct sock *newsmcsk = &new_smc->sk;
1003
1004         lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING);
1005         if (lsmc->sk.sk_state == SMC_LISTEN) {
1006                 smc_accept_enqueue(&lsmc->sk, newsmcsk);
1007         } else { /* no longer listening */
1008                 smc_close_non_accepted(newsmcsk);
1009         }
1010         release_sock(&lsmc->sk);
1011
1012         /* Wake up accept */
1013         lsmc->sk.sk_data_ready(&lsmc->sk);
1014         sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */
1015 }
1016
1017 /* listen worker: finish in state connected */
1018 static void smc_listen_out_connected(struct smc_sock *new_smc)
1019 {
1020         struct sock *newsmcsk = &new_smc->sk;
1021
1022         sk_refcnt_debug_inc(newsmcsk);
1023         if (newsmcsk->sk_state == SMC_INIT)
1024                 newsmcsk->sk_state = SMC_ACTIVE;
1025
1026         smc_listen_out(new_smc);
1027 }
1028
1029 /* listen worker: finish in error state */
1030 static void smc_listen_out_err(struct smc_sock *new_smc)
1031 {
1032         struct sock *newsmcsk = &new_smc->sk;
1033
1034         if (newsmcsk->sk_state == SMC_INIT)
1035                 sock_put(&new_smc->sk); /* passive closing */
1036         newsmcsk->sk_state = SMC_CLOSED;
1037         smc_conn_free(&new_smc->conn);
1038
1039         smc_listen_out(new_smc);
1040 }
1041
1042 /* listen worker: decline and fall back if possible */
1043 static void smc_listen_decline(struct smc_sock *new_smc, int reason_code,
1044                                int local_contact)
1045 {
1046         /* RDMA setup failed, switch back to TCP */
1047         if (local_contact == SMC_FIRST_CONTACT)
1048                 smc_lgr_forget(new_smc->conn.lgr);
1049         if (reason_code < 0) { /* error, no fallback possible */
1050                 smc_listen_out_err(new_smc);
1051                 return;
1052         }
1053         smc_conn_free(&new_smc->conn);
1054         new_smc->use_fallback = true;
1055         new_smc->fallback_rsn = reason_code;
1056         if (reason_code && reason_code != SMC_CLC_DECL_PEERDECL) {
1057                 if (smc_clc_send_decline(new_smc, reason_code) < 0) {
1058                         smc_listen_out_err(new_smc);
1059                         return;
1060                 }
1061         }
1062         smc_listen_out_connected(new_smc);
1063 }
1064
1065 /* listen worker: check prefixes */
1066 static int smc_listen_rdma_check(struct smc_sock *new_smc,
1067                                  struct smc_clc_msg_proposal *pclc)
1068 {
1069         struct smc_clc_msg_proposal_prefix *pclc_prfx;
1070         struct socket *newclcsock = new_smc->clcsock;
1071
1072         pclc_prfx = smc_clc_proposal_get_prefix(pclc);
1073         if (smc_clc_prfx_match(newclcsock, pclc_prfx))
1074                 return SMC_CLC_DECL_CNFERR;
1075
1076         return 0;
1077 }
1078
1079 /* listen worker: initialize connection and buffers */
1080 static int smc_listen_rdma_init(struct smc_sock *new_smc,
1081                                 struct smc_clc_msg_proposal *pclc,
1082                                 struct smc_ib_device *ibdev, u8 ibport,
1083                                 int *local_contact)
1084 {
1085         /* allocate connection / link group */
1086         *local_contact = smc_conn_create(new_smc, false, 0, ibdev, ibport,
1087                                          &pclc->lcl, NULL, 0);
1088         if (*local_contact < 0) {
1089                 if (*local_contact == -ENOMEM)
1090                         return SMC_CLC_DECL_MEM;/* insufficient memory*/
1091                 return SMC_CLC_DECL_INTERR; /* other error */
1092         }
1093
1094         /* create send buffer and rmb */
1095         if (smc_buf_create(new_smc, false))
1096                 return SMC_CLC_DECL_MEM;
1097
1098         return 0;
1099 }
1100
1101 /* listen worker: initialize connection and buffers for SMC-D */
1102 static int smc_listen_ism_init(struct smc_sock *new_smc,
1103                                struct smc_clc_msg_proposal *pclc,
1104                                struct smcd_dev *ismdev,
1105                                int *local_contact)
1106 {
1107         struct smc_clc_msg_smcd *pclc_smcd;
1108
1109         pclc_smcd = smc_get_clc_msg_smcd(pclc);
1110         *local_contact = smc_conn_create(new_smc, true, 0, NULL, 0, NULL,
1111                                          ismdev, pclc_smcd->gid);
1112         if (*local_contact < 0) {
1113                 if (*local_contact == -ENOMEM)
1114                         return SMC_CLC_DECL_MEM;/* insufficient memory*/
1115                 return SMC_CLC_DECL_INTERR; /* other error */
1116         }
1117
1118         /* Check if peer can be reached via ISM device */
1119         if (smc_ism_cantalk(new_smc->conn.lgr->peer_gid,
1120                             new_smc->conn.lgr->vlan_id,
1121                             new_smc->conn.lgr->smcd)) {
1122                 if (*local_contact == SMC_FIRST_CONTACT)
1123                         smc_lgr_forget(new_smc->conn.lgr);
1124                 smc_conn_free(&new_smc->conn);
1125                 return SMC_CLC_DECL_CNFERR;
1126         }
1127
1128         /* Create send and receive buffers */
1129         if (smc_buf_create(new_smc, true)) {
1130                 if (*local_contact == SMC_FIRST_CONTACT)
1131                         smc_lgr_forget(new_smc->conn.lgr);
1132                 smc_conn_free(&new_smc->conn);
1133                 return SMC_CLC_DECL_MEM;
1134         }
1135
1136         return 0;
1137 }
1138
1139 /* listen worker: register buffers */
1140 static int smc_listen_rdma_reg(struct smc_sock *new_smc, int local_contact)
1141 {
1142         struct smc_link *link = &new_smc->conn.lgr->lnk[SMC_SINGLE_LINK];
1143
1144         if (local_contact != SMC_FIRST_CONTACT) {
1145                 if (!new_smc->conn.rmb_desc->reused) {
1146                         if (smc_reg_rmb(link, new_smc->conn.rmb_desc, true))
1147                                 return SMC_CLC_DECL_ERR_REGRMB;
1148                 }
1149         }
1150         smc_rmb_sync_sg_for_device(&new_smc->conn);
1151
1152         return 0;
1153 }
1154
1155 /* listen worker: finish RDMA setup */
1156 static int smc_listen_rdma_finish(struct smc_sock *new_smc,
1157                                   struct smc_clc_msg_accept_confirm *cclc,
1158                                   int local_contact)
1159 {
1160         struct smc_link *link = &new_smc->conn.lgr->lnk[SMC_SINGLE_LINK];
1161         int reason_code = 0;
1162
1163         if (local_contact == SMC_FIRST_CONTACT)
1164                 smc_link_save_peer_info(link, cclc);
1165
1166         if (smc_rmb_rtoken_handling(&new_smc->conn, cclc)) {
1167                 reason_code = SMC_CLC_DECL_ERR_RTOK;
1168                 goto decline;
1169         }
1170
1171         if (local_contact == SMC_FIRST_CONTACT) {
1172                 if (smc_ib_ready_link(link)) {
1173                         reason_code = SMC_CLC_DECL_ERR_RDYLNK;
1174                         goto decline;
1175                 }
1176                 /* QP confirmation over RoCE fabric */
1177                 reason_code = smc_serv_conf_first_link(new_smc);
1178                 if (reason_code)
1179                         goto decline;
1180         }
1181         return 0;
1182
1183 decline:
1184         mutex_unlock(&smc_create_lgr_pending);
1185         smc_listen_decline(new_smc, reason_code, local_contact);
1186         return reason_code;
1187 }
1188
1189 /* setup for RDMA connection of server */
1190 static void smc_listen_work(struct work_struct *work)
1191 {
1192         struct smc_sock *new_smc = container_of(work, struct smc_sock,
1193                                                 smc_listen_work);
1194         struct socket *newclcsock = new_smc->clcsock;
1195         struct smc_clc_msg_accept_confirm cclc;
1196         struct smc_clc_msg_proposal *pclc;
1197         struct smc_ib_device *ibdev;
1198         bool ism_supported = false;
1199         struct smcd_dev *ismdev;
1200         u8 buf[SMC_CLC_MAX_LEN];
1201         int local_contact = 0;
1202         unsigned short vlan;
1203         int reason_code = 0;
1204         int rc = 0;
1205         u8 ibport;
1206
1207         if (new_smc->use_fallback) {
1208                 smc_listen_out_connected(new_smc);
1209                 return;
1210         }
1211
1212         /* check if peer is smc capable */
1213         if (!tcp_sk(newclcsock->sk)->syn_smc) {
1214                 new_smc->use_fallback = true;
1215                 new_smc->fallback_rsn = SMC_CLC_DECL_PEERNOSMC;
1216                 smc_listen_out_connected(new_smc);
1217                 return;
1218         }
1219
1220         /* do inband token exchange -
1221          * wait for and receive SMC Proposal CLC message
1222          */
1223         pclc = (struct smc_clc_msg_proposal *)&buf;
1224         reason_code = smc_clc_wait_msg(new_smc, pclc, SMC_CLC_MAX_LEN,
1225                                        SMC_CLC_PROPOSAL);
1226         if (reason_code) {
1227                 smc_listen_decline(new_smc, reason_code, 0);
1228                 return;
1229         }
1230
1231         /* IPSec connections opt out of SMC-R optimizations */
1232         if (using_ipsec(new_smc)) {
1233                 smc_listen_decline(new_smc, SMC_CLC_DECL_IPSEC, 0);
1234                 return;
1235         }
1236
1237         mutex_lock(&smc_create_lgr_pending);
1238         smc_close_init(new_smc);
1239         smc_rx_init(new_smc);
1240         smc_tx_init(new_smc);
1241
1242         /* check if ISM is available */
1243         if ((pclc->hdr.path == SMC_TYPE_D || pclc->hdr.path == SMC_TYPE_B) &&
1244             !smc_check_ism(new_smc, &ismdev) &&
1245             !smc_listen_ism_init(new_smc, pclc, ismdev, &local_contact)) {
1246                 ism_supported = true;
1247         }
1248
1249         /* check if RDMA is available */
1250         if (!ism_supported &&
1251             ((pclc->hdr.path != SMC_TYPE_R && pclc->hdr.path != SMC_TYPE_B) ||
1252              smc_vlan_by_tcpsk(new_smc->clcsock, &vlan) ||
1253              smc_check_rdma(new_smc, &ibdev, &ibport, vlan, NULL) ||
1254              smc_listen_rdma_check(new_smc, pclc) ||
1255              smc_listen_rdma_init(new_smc, pclc, ibdev, ibport,
1256                                   &local_contact) ||
1257              smc_listen_rdma_reg(new_smc, local_contact))) {
1258                 /* SMC not supported, decline */
1259                 mutex_unlock(&smc_create_lgr_pending);
1260                 smc_listen_decline(new_smc, SMC_CLC_DECL_MODEUNSUPP,
1261                                    local_contact);
1262                 return;
1263         }
1264
1265         /* send SMC Accept CLC message */
1266         rc = smc_clc_send_accept(new_smc, local_contact);
1267         if (rc) {
1268                 mutex_unlock(&smc_create_lgr_pending);
1269                 smc_listen_decline(new_smc, rc, local_contact);
1270                 return;
1271         }
1272
1273         /* receive SMC Confirm CLC message */
1274         reason_code = smc_clc_wait_msg(new_smc, &cclc, sizeof(cclc),
1275                                        SMC_CLC_CONFIRM);
1276         if (reason_code) {
1277                 mutex_unlock(&smc_create_lgr_pending);
1278                 smc_listen_decline(new_smc, reason_code, local_contact);
1279                 return;
1280         }
1281
1282         /* finish worker */
1283         if (!ism_supported) {
1284                 if (smc_listen_rdma_finish(new_smc, &cclc, local_contact))
1285                         return;
1286         }
1287         smc_conn_save_peer_info(new_smc, &cclc);
1288         mutex_unlock(&smc_create_lgr_pending);
1289         smc_listen_out_connected(new_smc);
1290 }
1291
1292 static void smc_tcp_listen_work(struct work_struct *work)
1293 {
1294         struct smc_sock *lsmc = container_of(work, struct smc_sock,
1295                                              tcp_listen_work);
1296         struct sock *lsk = &lsmc->sk;
1297         struct smc_sock *new_smc;
1298         int rc = 0;
1299
1300         lock_sock(lsk);
1301         while (lsk->sk_state == SMC_LISTEN) {
1302                 rc = smc_clcsock_accept(lsmc, &new_smc);
1303                 if (rc)
1304                         goto out;
1305                 if (!new_smc)
1306                         continue;
1307
1308                 new_smc->listen_smc = lsmc;
1309                 new_smc->use_fallback = lsmc->use_fallback;
1310                 new_smc->fallback_rsn = lsmc->fallback_rsn;
1311                 sock_hold(lsk); /* sock_put in smc_listen_work */
1312                 INIT_WORK(&new_smc->smc_listen_work, smc_listen_work);
1313                 smc_copy_sock_settings_to_smc(new_smc);
1314                 new_smc->sk.sk_sndbuf = lsmc->sk.sk_sndbuf;
1315                 new_smc->sk.sk_rcvbuf = lsmc->sk.sk_rcvbuf;
1316                 sock_hold(&new_smc->sk); /* sock_put in passive closing */
1317                 if (!schedule_work(&new_smc->smc_listen_work))
1318                         sock_put(&new_smc->sk);
1319         }
1320
1321 out:
1322         release_sock(lsk);
1323         sock_put(&lsmc->sk); /* sock_hold in smc_listen */
1324 }
1325
1326 static int smc_listen(struct socket *sock, int backlog)
1327 {
1328         struct sock *sk = sock->sk;
1329         struct smc_sock *smc;
1330         int rc;
1331
1332         smc = smc_sk(sk);
1333         lock_sock(sk);
1334
1335         rc = -EINVAL;
1336         if ((sk->sk_state != SMC_INIT) && (sk->sk_state != SMC_LISTEN))
1337                 goto out;
1338
1339         rc = 0;
1340         if (sk->sk_state == SMC_LISTEN) {
1341                 sk->sk_max_ack_backlog = backlog;
1342                 goto out;
1343         }
1344         /* some socket options are handled in core, so we could not apply
1345          * them to the clc socket -- copy smc socket options to clc socket
1346          */
1347         smc_copy_sock_settings_to_clc(smc);
1348         if (!smc->use_fallback)
1349                 tcp_sk(smc->clcsock->sk)->syn_smc = 1;
1350
1351         rc = kernel_listen(smc->clcsock, backlog);
1352         if (rc)
1353                 goto out;
1354         sk->sk_max_ack_backlog = backlog;
1355         sk->sk_ack_backlog = 0;
1356         sk->sk_state = SMC_LISTEN;
1357         INIT_WORK(&smc->tcp_listen_work, smc_tcp_listen_work);
1358         sock_hold(sk); /* sock_hold in tcp_listen_worker */
1359         if (!schedule_work(&smc->tcp_listen_work))
1360                 sock_put(sk);
1361
1362 out:
1363         release_sock(sk);
1364         return rc;
1365 }
1366
1367 static int smc_accept(struct socket *sock, struct socket *new_sock,
1368                       int flags, bool kern)
1369 {
1370         struct sock *sk = sock->sk, *nsk;
1371         DECLARE_WAITQUEUE(wait, current);
1372         struct smc_sock *lsmc;
1373         long timeo;
1374         int rc = 0;
1375
1376         lsmc = smc_sk(sk);
1377         sock_hold(sk); /* sock_put below */
1378         lock_sock(sk);
1379
1380         if (lsmc->sk.sk_state != SMC_LISTEN) {
1381                 rc = -EINVAL;
1382                 release_sock(sk);
1383                 goto out;
1384         }
1385
1386         /* Wait for an incoming connection */
1387         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
1388         add_wait_queue_exclusive(sk_sleep(sk), &wait);
1389         while (!(nsk = smc_accept_dequeue(sk, new_sock))) {
1390                 set_current_state(TASK_INTERRUPTIBLE);
1391                 if (!timeo) {
1392                         rc = -EAGAIN;
1393                         break;
1394                 }
1395                 release_sock(sk);
1396                 timeo = schedule_timeout(timeo);
1397                 /* wakeup by sk_data_ready in smc_listen_work() */
1398                 sched_annotate_sleep();
1399                 lock_sock(sk);
1400                 if (signal_pending(current)) {
1401                         rc = sock_intr_errno(timeo);
1402                         break;
1403                 }
1404         }
1405         set_current_state(TASK_RUNNING);
1406         remove_wait_queue(sk_sleep(sk), &wait);
1407
1408         if (!rc)
1409                 rc = sock_error(nsk);
1410         release_sock(sk);
1411         if (rc)
1412                 goto out;
1413
1414         if (lsmc->sockopt_defer_accept && !(flags & O_NONBLOCK)) {
1415                 /* wait till data arrives on the socket */
1416                 timeo = msecs_to_jiffies(lsmc->sockopt_defer_accept *
1417                                                                 MSEC_PER_SEC);
1418                 if (smc_sk(nsk)->use_fallback) {
1419                         struct sock *clcsk = smc_sk(nsk)->clcsock->sk;
1420
1421                         lock_sock(clcsk);
1422                         if (skb_queue_empty(&clcsk->sk_receive_queue))
1423                                 sk_wait_data(clcsk, &timeo, NULL);
1424                         release_sock(clcsk);
1425                 } else if (!atomic_read(&smc_sk(nsk)->conn.bytes_to_rcv)) {
1426                         lock_sock(nsk);
1427                         smc_rx_wait(smc_sk(nsk), &timeo, smc_rx_data_available);
1428                         release_sock(nsk);
1429                 }
1430         }
1431
1432 out:
1433         sock_put(sk); /* sock_hold above */
1434         return rc;
1435 }
1436
1437 static int smc_getname(struct socket *sock, struct sockaddr *addr,
1438                        int peer)
1439 {
1440         struct smc_sock *smc;
1441
1442         if (peer && (sock->sk->sk_state != SMC_ACTIVE) &&
1443             (sock->sk->sk_state != SMC_APPCLOSEWAIT1))
1444                 return -ENOTCONN;
1445
1446         smc = smc_sk(sock->sk);
1447
1448         return smc->clcsock->ops->getname(smc->clcsock, addr, peer);
1449 }
1450
1451 static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1452 {
1453         struct sock *sk = sock->sk;
1454         struct smc_sock *smc;
1455         int rc = -EPIPE;
1456
1457         smc = smc_sk(sk);
1458         lock_sock(sk);
1459         if ((sk->sk_state != SMC_ACTIVE) &&
1460             (sk->sk_state != SMC_APPCLOSEWAIT1) &&
1461             (sk->sk_state != SMC_INIT))
1462                 goto out;
1463
1464         if (msg->msg_flags & MSG_FASTOPEN) {
1465                 if (sk->sk_state == SMC_INIT) {
1466                         smc->use_fallback = true;
1467                         smc->fallback_rsn = SMC_CLC_DECL_OPTUNSUPP;
1468                 } else {
1469                         rc = -EINVAL;
1470                         goto out;
1471                 }
1472         }
1473
1474         if (smc->use_fallback)
1475                 rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len);
1476         else
1477                 rc = smc_tx_sendmsg(smc, msg, len);
1478 out:
1479         release_sock(sk);
1480         return rc;
1481 }
1482
1483 static int smc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
1484                        int flags)
1485 {
1486         struct sock *sk = sock->sk;
1487         struct smc_sock *smc;
1488         int rc = -ENOTCONN;
1489
1490         smc = smc_sk(sk);
1491         lock_sock(sk);
1492         if ((sk->sk_state == SMC_INIT) ||
1493             (sk->sk_state == SMC_LISTEN) ||
1494             (sk->sk_state == SMC_CLOSED))
1495                 goto out;
1496
1497         if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
1498                 rc = 0;
1499                 goto out;
1500         }
1501
1502         if (smc->use_fallback) {
1503                 rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags);
1504         } else {
1505                 msg->msg_namelen = 0;
1506                 rc = smc_rx_recvmsg(smc, msg, NULL, len, flags);
1507         }
1508
1509 out:
1510         release_sock(sk);
1511         return rc;
1512 }
1513
1514 static __poll_t smc_accept_poll(struct sock *parent)
1515 {
1516         struct smc_sock *isk = smc_sk(parent);
1517         __poll_t mask = 0;
1518
1519         spin_lock(&isk->accept_q_lock);
1520         if (!list_empty(&isk->accept_q))
1521                 mask = EPOLLIN | EPOLLRDNORM;
1522         spin_unlock(&isk->accept_q_lock);
1523
1524         return mask;
1525 }
1526
1527 static __poll_t smc_poll(struct file *file, struct socket *sock,
1528                              poll_table *wait)
1529 {
1530         struct sock *sk = sock->sk;
1531         __poll_t mask = 0;
1532         struct smc_sock *smc;
1533
1534         if (!sk)
1535                 return EPOLLNVAL;
1536
1537         smc = smc_sk(sock->sk);
1538         if (smc->use_fallback) {
1539                 /* delegate to CLC child sock */
1540                 mask = smc->clcsock->ops->poll(file, smc->clcsock, wait);
1541                 sk->sk_err = smc->clcsock->sk->sk_err;
1542                 if (sk->sk_err)
1543                         mask |= EPOLLERR;
1544         } else {
1545                 if (sk->sk_state != SMC_CLOSED)
1546                         sock_poll_wait(file, sock, wait);
1547                 if (sk->sk_err)
1548                         mask |= EPOLLERR;
1549                 if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
1550                     (sk->sk_state == SMC_CLOSED))
1551                         mask |= EPOLLHUP;
1552                 if (sk->sk_state == SMC_LISTEN) {
1553                         /* woken up by sk_data_ready in smc_listen_work() */
1554                         mask = smc_accept_poll(sk);
1555                 } else {
1556                         if (atomic_read(&smc->conn.sndbuf_space) ||
1557                             sk->sk_shutdown & SEND_SHUTDOWN) {
1558                                 mask |= EPOLLOUT | EPOLLWRNORM;
1559                         } else {
1560                                 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1561                                 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1562                         }
1563                         if (atomic_read(&smc->conn.bytes_to_rcv))
1564                                 mask |= EPOLLIN | EPOLLRDNORM;
1565                         if (sk->sk_shutdown & RCV_SHUTDOWN)
1566                                 mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
1567                         if (sk->sk_state == SMC_APPCLOSEWAIT1)
1568                                 mask |= EPOLLIN;
1569                         if (smc->conn.urg_state == SMC_URG_VALID)
1570                                 mask |= EPOLLPRI;
1571                 }
1572         }
1573
1574         return mask;
1575 }
1576
1577 static int smc_shutdown(struct socket *sock, int how)
1578 {
1579         struct sock *sk = sock->sk;
1580         struct smc_sock *smc;
1581         int rc = -EINVAL;
1582         int rc1 = 0;
1583
1584         smc = smc_sk(sk);
1585
1586         if ((how < SHUT_RD) || (how > SHUT_RDWR))
1587                 return rc;
1588
1589         lock_sock(sk);
1590
1591         rc = -ENOTCONN;
1592         if ((sk->sk_state != SMC_ACTIVE) &&
1593             (sk->sk_state != SMC_PEERCLOSEWAIT1) &&
1594             (sk->sk_state != SMC_PEERCLOSEWAIT2) &&
1595             (sk->sk_state != SMC_APPCLOSEWAIT1) &&
1596             (sk->sk_state != SMC_APPCLOSEWAIT2) &&
1597             (sk->sk_state != SMC_APPFINCLOSEWAIT))
1598                 goto out;
1599         if (smc->use_fallback) {
1600                 rc = kernel_sock_shutdown(smc->clcsock, how);
1601                 sk->sk_shutdown = smc->clcsock->sk->sk_shutdown;
1602                 if (sk->sk_shutdown == SHUTDOWN_MASK)
1603                         sk->sk_state = SMC_CLOSED;
1604                 goto out;
1605         }
1606         switch (how) {
1607         case SHUT_RDWR:         /* shutdown in both directions */
1608                 rc = smc_close_active(smc);
1609                 break;
1610         case SHUT_WR:
1611                 rc = smc_close_shutdown_write(smc);
1612                 break;
1613         case SHUT_RD:
1614                 rc = 0;
1615                 /* nothing more to do because peer is not involved */
1616                 break;
1617         }
1618         if (smc->clcsock)
1619                 rc1 = kernel_sock_shutdown(smc->clcsock, how);
1620         /* map sock_shutdown_cmd constants to sk_shutdown value range */
1621         sk->sk_shutdown |= how + 1;
1622
1623 out:
1624         release_sock(sk);
1625         return rc ? rc : rc1;
1626 }
1627
1628 static int smc_setsockopt(struct socket *sock, int level, int optname,
1629                           char __user *optval, unsigned int optlen)
1630 {
1631         struct sock *sk = sock->sk;
1632         struct smc_sock *smc;
1633         int val, rc;
1634
1635         smc = smc_sk(sk);
1636
1637         /* generic setsockopts reaching us here always apply to the
1638          * CLC socket
1639          */
1640         rc = smc->clcsock->ops->setsockopt(smc->clcsock, level, optname,
1641                                            optval, optlen);
1642         if (smc->clcsock->sk->sk_err) {
1643                 sk->sk_err = smc->clcsock->sk->sk_err;
1644                 sk->sk_error_report(sk);
1645         }
1646         if (rc)
1647                 return rc;
1648
1649         if (optlen < sizeof(int))
1650                 return -EINVAL;
1651         if (get_user(val, (int __user *)optval))
1652                 return -EFAULT;
1653
1654         lock_sock(sk);
1655         switch (optname) {
1656         case TCP_ULP:
1657         case TCP_FASTOPEN:
1658         case TCP_FASTOPEN_CONNECT:
1659         case TCP_FASTOPEN_KEY:
1660         case TCP_FASTOPEN_NO_COOKIE:
1661                 /* option not supported by SMC */
1662                 if (sk->sk_state == SMC_INIT) {
1663                         smc->use_fallback = true;
1664                         smc->fallback_rsn = SMC_CLC_DECL_OPTUNSUPP;
1665                 } else {
1666                         if (!smc->use_fallback)
1667                                 rc = -EINVAL;
1668                 }
1669                 break;
1670         case TCP_NODELAY:
1671                 if (sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) {
1672                         if (val && !smc->use_fallback)
1673                                 mod_delayed_work(system_wq, &smc->conn.tx_work,
1674                                                  0);
1675                 }
1676                 break;
1677         case TCP_CORK:
1678                 if (sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) {
1679                         if (!val && !smc->use_fallback)
1680                                 mod_delayed_work(system_wq, &smc->conn.tx_work,
1681                                                  0);
1682                 }
1683                 break;
1684         case TCP_DEFER_ACCEPT:
1685                 smc->sockopt_defer_accept = val;
1686                 break;
1687         default:
1688                 break;
1689         }
1690         release_sock(sk);
1691
1692         return rc;
1693 }
1694
1695 static int smc_getsockopt(struct socket *sock, int level, int optname,
1696                           char __user *optval, int __user *optlen)
1697 {
1698         struct smc_sock *smc;
1699
1700         smc = smc_sk(sock->sk);
1701         /* socket options apply to the CLC socket */
1702         return smc->clcsock->ops->getsockopt(smc->clcsock, level, optname,
1703                                              optval, optlen);
1704 }
1705
1706 static int smc_ioctl(struct socket *sock, unsigned int cmd,
1707                      unsigned long arg)
1708 {
1709         union smc_host_cursor cons, urg;
1710         struct smc_connection *conn;
1711         struct smc_sock *smc;
1712         int answ;
1713
1714         smc = smc_sk(sock->sk);
1715         conn = &smc->conn;
1716         lock_sock(&smc->sk);
1717         if (smc->use_fallback) {
1718                 if (!smc->clcsock) {
1719                         release_sock(&smc->sk);
1720                         return -EBADF;
1721                 }
1722                 answ = smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg);
1723                 release_sock(&smc->sk);
1724                 return answ;
1725         }
1726         switch (cmd) {
1727         case SIOCINQ: /* same as FIONREAD */
1728                 if (smc->sk.sk_state == SMC_LISTEN) {
1729                         release_sock(&smc->sk);
1730                         return -EINVAL;
1731                 }
1732                 if (smc->sk.sk_state == SMC_INIT ||
1733                     smc->sk.sk_state == SMC_CLOSED)
1734                         answ = 0;
1735                 else
1736                         answ = atomic_read(&smc->conn.bytes_to_rcv);
1737                 break;
1738         case SIOCOUTQ:
1739                 /* output queue size (not send + not acked) */
1740                 if (smc->sk.sk_state == SMC_LISTEN) {
1741                         release_sock(&smc->sk);
1742                         return -EINVAL;
1743                 }
1744                 if (smc->sk.sk_state == SMC_INIT ||
1745                     smc->sk.sk_state == SMC_CLOSED)
1746                         answ = 0;
1747                 else
1748                         answ = smc->conn.sndbuf_desc->len -
1749                                         atomic_read(&smc->conn.sndbuf_space);
1750                 break;
1751         case SIOCOUTQNSD:
1752                 /* output queue size (not send only) */
1753                 if (smc->sk.sk_state == SMC_LISTEN) {
1754                         release_sock(&smc->sk);
1755                         return -EINVAL;
1756                 }
1757                 if (smc->sk.sk_state == SMC_INIT ||
1758                     smc->sk.sk_state == SMC_CLOSED)
1759                         answ = 0;
1760                 else
1761                         answ = smc_tx_prepared_sends(&smc->conn);
1762                 break;
1763         case SIOCATMARK:
1764                 if (smc->sk.sk_state == SMC_LISTEN) {
1765                         release_sock(&smc->sk);
1766                         return -EINVAL;
1767                 }
1768                 if (smc->sk.sk_state == SMC_INIT ||
1769                     smc->sk.sk_state == SMC_CLOSED) {
1770                         answ = 0;
1771                 } else {
1772                         smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
1773                         smc_curs_copy(&urg, &conn->urg_curs, conn);
1774                         answ = smc_curs_diff(conn->rmb_desc->len,
1775                                              &cons, &urg) == 1;
1776                 }
1777                 break;
1778         default:
1779                 release_sock(&smc->sk);
1780                 return -ENOIOCTLCMD;
1781         }
1782         release_sock(&smc->sk);
1783
1784         return put_user(answ, (int __user *)arg);
1785 }
1786
1787 static ssize_t smc_sendpage(struct socket *sock, struct page *page,
1788                             int offset, size_t size, int flags)
1789 {
1790         struct sock *sk = sock->sk;
1791         struct smc_sock *smc;
1792         int rc = -EPIPE;
1793
1794         smc = smc_sk(sk);
1795         lock_sock(sk);
1796         if (sk->sk_state != SMC_ACTIVE) {
1797                 release_sock(sk);
1798                 goto out;
1799         }
1800         release_sock(sk);
1801         if (smc->use_fallback)
1802                 rc = kernel_sendpage(smc->clcsock, page, offset,
1803                                      size, flags);
1804         else
1805                 rc = sock_no_sendpage(sock, page, offset, size, flags);
1806
1807 out:
1808         return rc;
1809 }
1810
1811 /* Map the affected portions of the rmbe into an spd, note the number of bytes
1812  * to splice in conn->splice_pending, and press 'go'. Delays consumer cursor
1813  * updates till whenever a respective page has been fully processed.
1814  * Note that subsequent recv() calls have to wait till all splice() processing
1815  * completed.
1816  */
1817 static ssize_t smc_splice_read(struct socket *sock, loff_t *ppos,
1818                                struct pipe_inode_info *pipe, size_t len,
1819                                unsigned int flags)
1820 {
1821         struct sock *sk = sock->sk;
1822         struct smc_sock *smc;
1823         int rc = -ENOTCONN;
1824
1825         smc = smc_sk(sk);
1826         lock_sock(sk);
1827
1828         if (sk->sk_state == SMC_INIT ||
1829             sk->sk_state == SMC_LISTEN ||
1830             sk->sk_state == SMC_CLOSED)
1831                 goto out;
1832
1833         if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
1834                 rc = 0;
1835                 goto out;
1836         }
1837
1838         if (smc->use_fallback) {
1839                 rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos,
1840                                                     pipe, len, flags);
1841         } else {
1842                 if (*ppos) {
1843                         rc = -ESPIPE;
1844                         goto out;
1845                 }
1846                 if (flags & SPLICE_F_NONBLOCK)
1847                         flags = MSG_DONTWAIT;
1848                 else
1849                         flags = 0;
1850                 rc = smc_rx_recvmsg(smc, NULL, pipe, len, flags);
1851         }
1852 out:
1853         release_sock(sk);
1854
1855         return rc;
1856 }
1857
1858 /* must look like tcp */
1859 static const struct proto_ops smc_sock_ops = {
1860         .family         = PF_SMC,
1861         .owner          = THIS_MODULE,
1862         .release        = smc_release,
1863         .bind           = smc_bind,
1864         .connect        = smc_connect,
1865         .socketpair     = sock_no_socketpair,
1866         .accept         = smc_accept,
1867         .getname        = smc_getname,
1868         .poll           = smc_poll,
1869         .ioctl          = smc_ioctl,
1870         .listen         = smc_listen,
1871         .shutdown       = smc_shutdown,
1872         .setsockopt     = smc_setsockopt,
1873         .getsockopt     = smc_getsockopt,
1874         .sendmsg        = smc_sendmsg,
1875         .recvmsg        = smc_recvmsg,
1876         .mmap           = sock_no_mmap,
1877         .sendpage       = smc_sendpage,
1878         .splice_read    = smc_splice_read,
1879 };
1880
1881 static int smc_create(struct net *net, struct socket *sock, int protocol,
1882                       int kern)
1883 {
1884         int family = (protocol == SMCPROTO_SMC6) ? PF_INET6 : PF_INET;
1885         struct smc_sock *smc;
1886         struct sock *sk;
1887         int rc;
1888
1889         rc = -ESOCKTNOSUPPORT;
1890         if (sock->type != SOCK_STREAM)
1891                 goto out;
1892
1893         rc = -EPROTONOSUPPORT;
1894         if (protocol != SMCPROTO_SMC && protocol != SMCPROTO_SMC6)
1895                 goto out;
1896
1897         rc = -ENOBUFS;
1898         sock->ops = &smc_sock_ops;
1899         sk = smc_sock_alloc(net, sock, protocol);
1900         if (!sk)
1901                 goto out;
1902
1903         /* create internal TCP socket for CLC handshake and fallback */
1904         smc = smc_sk(sk);
1905         smc->use_fallback = false; /* assume rdma capability first */
1906         smc->fallback_rsn = 0;
1907         rc = sock_create_kern(net, family, SOCK_STREAM, IPPROTO_TCP,
1908                               &smc->clcsock);
1909         if (rc) {
1910                 sk_common_release(sk);
1911                 goto out;
1912         }
1913         smc->sk.sk_sndbuf = max(smc->clcsock->sk->sk_sndbuf, SMC_BUF_MIN_SIZE);
1914         smc->sk.sk_rcvbuf = max(smc->clcsock->sk->sk_rcvbuf, SMC_BUF_MIN_SIZE);
1915
1916 out:
1917         return rc;
1918 }
1919
1920 static const struct net_proto_family smc_sock_family_ops = {
1921         .family = PF_SMC,
1922         .owner  = THIS_MODULE,
1923         .create = smc_create,
1924 };
1925
1926 static int __init smc_init(void)
1927 {
1928         int rc;
1929
1930         rc = smc_pnet_init();
1931         if (rc)
1932                 return rc;
1933
1934         rc = smc_llc_init();
1935         if (rc) {
1936                 pr_err("%s: smc_llc_init fails with %d\n", __func__, rc);
1937                 goto out_pnet;
1938         }
1939
1940         rc = smc_cdc_init();
1941         if (rc) {
1942                 pr_err("%s: smc_cdc_init fails with %d\n", __func__, rc);
1943                 goto out_pnet;
1944         }
1945
1946         rc = proto_register(&smc_proto, 1);
1947         if (rc) {
1948                 pr_err("%s: proto_register(v4) fails with %d\n", __func__, rc);
1949                 goto out_pnet;
1950         }
1951
1952         rc = proto_register(&smc_proto6, 1);
1953         if (rc) {
1954                 pr_err("%s: proto_register(v6) fails with %d\n", __func__, rc);
1955                 goto out_proto;
1956         }
1957
1958         rc = sock_register(&smc_sock_family_ops);
1959         if (rc) {
1960                 pr_err("%s: sock_register fails with %d\n", __func__, rc);
1961                 goto out_proto6;
1962         }
1963         INIT_HLIST_HEAD(&smc_v4_hashinfo.ht);
1964         INIT_HLIST_HEAD(&smc_v6_hashinfo.ht);
1965
1966         rc = smc_ib_register_client();
1967         if (rc) {
1968                 pr_err("%s: ib_register fails with %d\n", __func__, rc);
1969                 goto out_sock;
1970         }
1971
1972         static_branch_enable(&tcp_have_smc);
1973         return 0;
1974
1975 out_sock:
1976         sock_unregister(PF_SMC);
1977 out_proto6:
1978         proto_unregister(&smc_proto6);
1979 out_proto:
1980         proto_unregister(&smc_proto);
1981 out_pnet:
1982         smc_pnet_exit();
1983         return rc;
1984 }
1985
1986 static void __exit smc_exit(void)
1987 {
1988         smc_core_exit();
1989         static_branch_disable(&tcp_have_smc);
1990         smc_ib_unregister_client();
1991         sock_unregister(PF_SMC);
1992         proto_unregister(&smc_proto6);
1993         proto_unregister(&smc_proto);
1994         smc_pnet_exit();
1995 }
1996
1997 module_init(smc_init);
1998 module_exit(smc_exit);
1999
2000 MODULE_AUTHOR("Ursula Braun <[email protected]>");
2001 MODULE_DESCRIPTION("smc socket address family");
2002 MODULE_LICENSE("GPL");
2003 MODULE_ALIAS_NETPROTO(PF_SMC);