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 <ubraun@linux.vnet.ibm.com>
  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         if (smc->connect_info && sk->sk_state == SMC_INIT)
 131                 tcp_abort(smc->clcsock->sk, ECONNABORTED);
 132         flush_work(&smc->connect_work);
 133         kfree(smc->connect_info);
 134         smc->connect_info = NULL;
 135
 136         if (sk->sk_state == SMC_LISTEN)
 137                 /* smc_close_non_accepted() is called and acquires
 138                  * sock lock for child sockets again
 139                  */
 140                 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 141         else
 142                 lock_sock(sk);
 143
 144         if (!smc->use_fallback) {
 145                 rc = smc_close_active(smc);
 146                 sock_set_flag(sk, SOCK_DEAD);
 147                 sk->sk_shutdown |= SHUTDOWN_MASK;
 148         }
 149         if (smc->clcsock) {
 150                 sock_release(smc->clcsock);
 151                 smc->clcsock = NULL;
 152         }
 153         if (smc->use_fallback) {
 154                 if (sk->sk_state != SMC_LISTEN && sk->sk_state != SMC_INIT)
 155                         sock_put(sk); /* passive closing */
 156                 sk->sk_state = SMC_CLOSED;
 157                 sk->sk_state_change(sk);
 158         }
 159
 160         /* detach socket */
 161         sock_orphan(sk);
 162         sock->sk = NULL;
 163         if (!smc->use_fallback && sk->sk_state == SMC_CLOSED)
 164                 smc_conn_free(&smc->conn);
 165         release_sock(sk);
 166
 167         sk->sk_prot->unhash(sk);
 168         sock_put(sk); /* final sock_put */
 169 out:
 170         return rc;
 171 }
 172
 173 static void smc_destruct(struct sock *sk)
 174 {
 175         if (sk->sk_state != SMC_CLOSED)
 176                 return;
 177         if (!sock_flag(sk, SOCK_DEAD))
 178                 return;
 179
 180         sk_refcnt_debug_dec(sk);
 181 }
 182
 183 static struct sock *smc_sock_alloc(struct net *net, struct socket *sock,
 184                                    int protocol)
 185 {
 186         struct smc_sock *smc;
 187         struct proto *prot;
 188         struct sock *sk;
 189
 190         prot = (protocol == SMCPROTO_SMC6) ? &smc_proto6 : &smc_proto;
 191         sk = sk_alloc(net, PF_SMC, GFP_KERNEL, prot, 0);
 192         if (!sk)
 193                 return NULL;
 194
 195         sock_init_data(sock, sk); /* sets sk_refcnt to 1 */
 196         sk->sk_state = SMC_INIT;
 197         sk->sk_destruct = smc_destruct;
 198         sk->sk_protocol = protocol;
 199         smc = smc_sk(sk);
 200         INIT_WORK(&smc->tcp_listen_work, smc_tcp_listen_work);
 201         INIT_WORK(&smc->connect_work, smc_connect_work);
 202         INIT_DELAYED_WORK(&smc->conn.tx_work, smc_tx_work);
 203         INIT_LIST_HEAD(&smc->accept_q);
 204         spin_lock_init(&smc->accept_q_lock);
 205         spin_lock_init(&smc->conn.send_lock);
 206         sk->sk_prot->hash(sk);
 207         sk_refcnt_debug_inc(sk);
 208
 209         return sk;
 210 }
 211
 212 static int smc_bind(struct socket *sock, struct sockaddr *uaddr,
 213                     int addr_len)
 214 {
 215         struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
 216         struct sock *sk = sock->sk;
 217         struct smc_sock *smc;
 218         int rc;
 219
 220         smc = smc_sk(sk);
 221
 222         /* replicate tests from inet_bind(), to be safe wrt. future changes */
 223         rc = -EINVAL;
 224         if (addr_len < sizeof(struct sockaddr_in))
 225                 goto out;
 226
 227         rc = -EAFNOSUPPORT;
 228         if (addr->sin_family != AF_INET &&
 229             addr->sin_family != AF_INET6 &&
 230             addr->sin_family != AF_UNSPEC)
 231                 goto out;
 232         /* accept AF_UNSPEC (mapped to AF_INET) only if s_addr is INADDR_ANY */
 233         if (addr->sin_family == AF_UNSPEC &&
 234             addr->sin_addr.s_addr != htonl(INADDR_ANY))
 235                 goto out;
 236
 237         lock_sock(sk);
 238
 239         /* Check if socket is already active */
 240         rc = -EINVAL;
 241         if (sk->sk_state != SMC_INIT)
 242                 goto out_rel;
 243
 244         smc->clcsock->sk->sk_reuse = sk->sk_reuse;
 245         rc = kernel_bind(smc->clcsock, uaddr, addr_len);
 246
 247 out_rel:
 248         release_sock(sk);
 249 out:
 250         return rc;
 251 }
 252
 253 static void smc_copy_sock_settings(struct sock *nsk, struct sock *osk,
 254                                    unsigned long mask)
 255 {
 256         /* options we don't get control via setsockopt for */
 257         nsk->sk_type = osk->sk_type;
 258         nsk->sk_sndbuf = osk->sk_sndbuf;
 259         nsk->sk_rcvbuf = osk->sk_rcvbuf;
 260         nsk->sk_sndtimeo = osk->sk_sndtimeo;
 261         nsk->sk_rcvtimeo = osk->sk_rcvtimeo;
 262         nsk->sk_mark = osk->sk_mark;
 263         nsk->sk_priority = osk->sk_priority;
 264         nsk->sk_rcvlowat = osk->sk_rcvlowat;
 265         nsk->sk_bound_dev_if = osk->sk_bound_dev_if;
 266         nsk->sk_err = osk->sk_err;
 267
 268         nsk->sk_flags &= ~mask;
 269         nsk->sk_flags |= osk->sk_flags & mask;
 270 }
 271
 272 #define SK_FLAGS_SMC_TO_CLC ((1UL << SOCK_URGINLINE) | \
 273                              (1UL << SOCK_KEEPOPEN) | \
 274                              (1UL << SOCK_LINGER) | \
 275                              (1UL << SOCK_BROADCAST) | \
 276                              (1UL << SOCK_TIMESTAMP) | \
 277                              (1UL << SOCK_DBG) | \
 278                              (1UL << SOCK_RCVTSTAMP) | \
 279                              (1UL << SOCK_RCVTSTAMPNS) | \
 280                              (1UL << SOCK_LOCALROUTE) | \
 281                              (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
 282                              (1UL << SOCK_RXQ_OVFL) | \
 283                              (1UL << SOCK_WIFI_STATUS) | \
 284                              (1UL << SOCK_NOFCS) | \
 285                              (1UL << SOCK_FILTER_LOCKED))
 286 /* copy only relevant settings and flags of SOL_SOCKET level from smc to
 287  * clc socket (since smc is not called for these options from net/core)
 288  */
 289 static void smc_copy_sock_settings_to_clc(struct smc_sock *smc)
 290 {
 291         smc_copy_sock_settings(smc->clcsock->sk, &smc->sk, SK_FLAGS_SMC_TO_CLC);
 292 }
 293
 294 #define SK_FLAGS_CLC_TO_SMC ((1UL << SOCK_URGINLINE) | \
 295                              (1UL << SOCK_KEEPOPEN) | \
 296                              (1UL << SOCK_LINGER) | \
 297                              (1UL << SOCK_DBG))
 298 /* copy only settings and flags relevant for smc from clc to smc socket */
 299 static void smc_copy_sock_settings_to_smc(struct smc_sock *smc)
 300 {
 301         smc_copy_sock_settings(&smc->sk, smc->clcsock->sk, SK_FLAGS_CLC_TO_SMC);
 302 }
 303
 304 /* register a new rmb, optionally send confirm_rkey msg to register with peer */
 305 static int smc_reg_rmb(struct smc_link *link, struct smc_buf_desc *rmb_desc,
 306                        bool conf_rkey)
 307 {
 308         /* register memory region for new rmb */
 309         if (smc_wr_reg_send(link, rmb_desc->mr_rx[SMC_SINGLE_LINK])) {
 310                 rmb_desc->regerr = 1;
 311                 return -EFAULT;
 312         }
 313         if (!conf_rkey)
 314                 return 0;
 315         /* exchange confirm_rkey msg with peer */
 316         if (smc_llc_do_confirm_rkey(link, rmb_desc)) {
 317                 rmb_desc->regerr = 1;
 318                 return -EFAULT;
 319         }
 320         return 0;
 321 }
 322
 323 static int smc_clnt_conf_first_link(struct smc_sock *smc)
 324 {
 325         struct net *net = sock_net(smc->clcsock->sk);
 326         struct smc_link_group *lgr = smc->conn.lgr;
 327         struct smc_link *link;
 328         int rest;
 329         int rc;
 330
 331         link = &lgr->lnk[SMC_SINGLE_LINK];
 332         /* receive CONFIRM LINK request from server over RoCE fabric */
 333         rest = wait_for_completion_interruptible_timeout(
 334                 &link->llc_confirm,
 335                 SMC_LLC_WAIT_FIRST_TIME);
 336         if (rest <= 0) {
 337                 struct smc_clc_msg_decline dclc;
 338
 339                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
 340                                       SMC_CLC_DECLINE);
 341                 return rc;
 342         }
 343
 344         if (link->llc_confirm_rc)
 345                 return SMC_CLC_DECL_RMBE_EC;
 346
 347         rc = smc_ib_modify_qp_rts(link);
 348         if (rc)
 349                 return SMC_CLC_DECL_ERR_RDYLNK;
 350
 351         smc_wr_remember_qp_attr(link);
 352
 353         if (smc_reg_rmb(link, smc->conn.rmb_desc, false))
 354                 return SMC_CLC_DECL_ERR_REGRMB;
 355
 356         /* send CONFIRM LINK response over RoCE fabric */
 357         rc = smc_llc_send_confirm_link(link, SMC_LLC_RESP);
 358         if (rc < 0)
 359                 return SMC_CLC_DECL_TIMEOUT_CL;
 360
 361         /* receive ADD LINK request from server over RoCE fabric */
 362         rest = wait_for_completion_interruptible_timeout(&link->llc_add,
 363                                                          SMC_LLC_WAIT_TIME);
 364         if (rest <= 0) {
 365                 struct smc_clc_msg_decline dclc;
 366
 367                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
 368                                       SMC_CLC_DECLINE);
 369                 return rc;
 370         }
 371
 372         /* send add link reject message, only one link supported for now */
 373         rc = smc_llc_send_add_link(link,
 374                                    link->smcibdev->mac[link->ibport - 1],
 375                                    link->gid, SMC_LLC_RESP);
 376         if (rc < 0)
 377                 return SMC_CLC_DECL_TIMEOUT_AL;
 378
 379         smc_llc_link_active(link, net->ipv4.sysctl_tcp_keepalive_time);
 380
 381         return 0;
 382 }
 383
 384 static void smcr_conn_save_peer_info(struct smc_sock *smc,
 385                                      struct smc_clc_msg_accept_confirm *clc)
 386 {
 387         int bufsize = smc_uncompress_bufsize(clc->rmbe_size);
 388
 389         smc->conn.peer_rmbe_idx = clc->rmbe_idx;
 390         smc->conn.local_tx_ctrl.token = ntohl(clc->rmbe_alert_token);
 391         smc->conn.peer_rmbe_size = bufsize;
 392         atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
 393         smc->conn.tx_off = bufsize * (smc->conn.peer_rmbe_idx - 1);
 394 }
 395
 396 static void smcd_conn_save_peer_info(struct smc_sock *smc,
 397                                      struct smc_clc_msg_accept_confirm *clc)
 398 {
 399         int bufsize = smc_uncompress_bufsize(clc->dmbe_size);
 400
 401         smc->conn.peer_rmbe_idx = clc->dmbe_idx;
 402         smc->conn.peer_token = clc->token;
 403         /* msg header takes up space in the buffer */
 404         smc->conn.peer_rmbe_size = bufsize - sizeof(struct smcd_cdc_msg);
 405         atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
 406         smc->conn.tx_off = bufsize * smc->conn.peer_rmbe_idx;
 407 }
 408
 409 static void smc_conn_save_peer_info(struct smc_sock *smc,
 410                                     struct smc_clc_msg_accept_confirm *clc)
 411 {
 412         if (smc->conn.lgr->is_smcd)
 413                 smcd_conn_save_peer_info(smc, clc);
 414         else
 415                 smcr_conn_save_peer_info(smc, clc);
 416 }
 417
 418 static void smc_link_save_peer_info(struct smc_link *link,
 419                                     struct smc_clc_msg_accept_confirm *clc)
 420 {
 421         link->peer_qpn = ntoh24(clc->qpn);
 422         memcpy(link->peer_gid, clc->lcl.gid, SMC_GID_SIZE);
 423         memcpy(link->peer_mac, clc->lcl.mac, sizeof(link->peer_mac));
 424         link->peer_psn = ntoh24(clc->psn);
 425         link->peer_mtu = clc->qp_mtu;
 426 }
 427
 428 /* fall back during connect */
 429 static int smc_connect_fallback(struct smc_sock *smc, int reason_code)
 430 {
 431         smc->use_fallback = true;
 432         smc->fallback_rsn = reason_code;
 433         smc_copy_sock_settings_to_clc(smc);
 434         if (smc->sk.sk_state == SMC_INIT)
 435                 smc->sk.sk_state = SMC_ACTIVE;
 436         return 0;
 437 }
 438
 439 /* decline and fall back during connect */
 440 static int smc_connect_decline_fallback(struct smc_sock *smc, int reason_code)
 441 {
 442         int rc;
 443
 444         if (reason_code < 0) { /* error, fallback is not possible */
 445                 if (smc->sk.sk_state == SMC_INIT)
 446                         sock_put(&smc->sk); /* passive closing */
 447                 return reason_code;
 448         }
 449         if (reason_code != SMC_CLC_DECL_PEERDECL) {
 450                 rc = smc_clc_send_decline(smc, reason_code);
 451                 if (rc < 0) {
 452                         if (smc->sk.sk_state == SMC_INIT)
 453                                 sock_put(&smc->sk); /* passive closing */
 454                         return rc;
 455                 }
 456         }
 457         return smc_connect_fallback(smc, reason_code);
 458 }
 459
 460 /* abort connecting */
 461 static int smc_connect_abort(struct smc_sock *smc, int reason_code,
 462                              int local_contact)
 463 {
 464         if (local_contact == SMC_FIRST_CONTACT)
 465                 smc_lgr_forget(smc->conn.lgr);
 466         mutex_unlock(&smc_create_lgr_pending);
 467         smc_conn_free(&smc->conn);
 468         return reason_code;
 469 }
 470
 471 /* check if there is a rdma device available for this connection. */
 472 /* called for connect and listen */
 473 static int smc_check_rdma(struct smc_sock *smc, struct smc_ib_device **ibdev,
 474                           u8 *ibport, unsigned short vlan_id, u8 gid[])
 475 {
 476         int reason_code = 0;
 477
 478         /* PNET table look up: search active ib_device and port
 479          * within same PNETID that also contains the ethernet device
 480          * used for the internal TCP socket
 481          */
 482         smc_pnet_find_roce_resource(smc->clcsock->sk, ibdev, ibport, vlan_id,
 483                                     gid);
 484         if (!(*ibdev))
 485                 reason_code = SMC_CLC_DECL_CNFERR; /* configuration error */
 486
 487         return reason_code;
 488 }
 489
 490 /* check if there is an ISM device available for this connection. */
 491 /* called for connect and listen */
 492 static int smc_check_ism(struct smc_sock *smc, struct smcd_dev **ismdev)
 493 {
 494         /* Find ISM device with same PNETID as connecting interface  */
 495         smc_pnet_find_ism_resource(smc->clcsock->sk, ismdev);
 496         if (!(*ismdev))
 497                 return SMC_CLC_DECL_CNFERR; /* configuration error */
 498         return 0;
 499 }
 500
 501 /* Check for VLAN ID and register it on ISM device just for CLC handshake */
 502 static int smc_connect_ism_vlan_setup(struct smc_sock *smc,
 503                                       struct smcd_dev *ismdev,
 504                                       unsigned short vlan_id)
 505 {
 506         if (vlan_id && smc_ism_get_vlan(ismdev, vlan_id))
 507                 return SMC_CLC_DECL_CNFERR;
 508         return 0;
 509 }
 510
 511 /* cleanup temporary VLAN ID registration used for CLC handshake. If ISM is
 512  * used, the VLAN ID will be registered again during the connection setup.
 513  */
 514 static int smc_connect_ism_vlan_cleanup(struct smc_sock *smc, bool is_smcd,
 515                                         struct smcd_dev *ismdev,
 516                                         unsigned short vlan_id)
 517 {
 518         if (!is_smcd)
 519                 return 0;
 520         if (vlan_id && smc_ism_put_vlan(ismdev, vlan_id))
 521                 return SMC_CLC_DECL_CNFERR;
 522         return 0;
 523 }
 524
 525 /* CLC handshake during connect */
 526 static int smc_connect_clc(struct smc_sock *smc, int smc_type,
 527                            struct smc_clc_msg_accept_confirm *aclc,
 528                            struct smc_ib_device *ibdev, u8 ibport,
 529                            u8 gid[], struct smcd_dev *ismdev)
 530 {
 531         int rc = 0;
 532
 533         /* do inband token exchange */
 534         rc = smc_clc_send_proposal(smc, smc_type, ibdev, ibport, gid, ismdev);
 535         if (rc)
 536                 return rc;
 537         /* receive SMC Accept CLC message */
 538         return smc_clc_wait_msg(smc, aclc, sizeof(*aclc), SMC_CLC_ACCEPT);
 539 }
 540
 541 /* setup for RDMA connection of client */
 542 static int smc_connect_rdma(struct smc_sock *smc,
 543                             struct smc_clc_msg_accept_confirm *aclc,
 544                             struct smc_ib_device *ibdev, u8 ibport)
 545 {
 546         int local_contact = SMC_FIRST_CONTACT;
 547         struct smc_link *link;
 548         int reason_code = 0;
 549
 550         mutex_lock(&smc_create_lgr_pending);
 551         local_contact = smc_conn_create(smc, false, aclc->hdr.flag, ibdev,
 552                                         ibport, ntoh24(aclc->qpn), &aclc->lcl,
 553                                         NULL, 0);
 554         if (local_contact < 0) {
 555                 if (local_contact == -ENOMEM)
 556                         reason_code = SMC_CLC_DECL_MEM;/* insufficient memory*/
 557                 else if (local_contact == -ENOLINK)
 558                         reason_code = SMC_CLC_DECL_SYNCERR; /* synchr. error */
 559                 else
 560                         reason_code = SMC_CLC_DECL_INTERR; /* other error */
 561                 return smc_connect_abort(smc, reason_code, 0);
 562         }
 563         link = &smc->conn.lgr->lnk[SMC_SINGLE_LINK];
 564
 565         smc_conn_save_peer_info(smc, aclc);
 566
 567         /* create send buffer and rmb */
 568         if (smc_buf_create(smc, false))
 569                 return smc_connect_abort(smc, SMC_CLC_DECL_MEM, local_contact);
 570
 571         if (local_contact == SMC_FIRST_CONTACT)
 572                 smc_link_save_peer_info(link, aclc);
 573
 574         if (smc_rmb_rtoken_handling(&smc->conn, aclc))
 575                 return smc_connect_abort(smc, SMC_CLC_DECL_ERR_RTOK,
 576                                          local_contact);
 577
 578         smc_close_init(smc);
 579         smc_rx_init(smc);
 580
 581         if (local_contact == SMC_FIRST_CONTACT) {
 582                 if (smc_ib_ready_link(link))
 583                         return smc_connect_abort(smc, SMC_CLC_DECL_ERR_RDYLNK,
 584                                                  local_contact);
 585         } else {
 586                 if (!smc->conn.rmb_desc->reused &&
 587                     smc_reg_rmb(link, smc->conn.rmb_desc, true))
 588                         return smc_connect_abort(smc, SMC_CLC_DECL_ERR_REGRMB,
 589                                                  local_contact);
 590         }
 591         smc_rmb_sync_sg_for_device(&smc->conn);
 592
 593         reason_code = smc_clc_send_confirm(smc);
 594         if (reason_code)
 595                 return smc_connect_abort(smc, reason_code, local_contact);
 596
 597         smc_tx_init(smc);
 598
 599         if (local_contact == SMC_FIRST_CONTACT) {
 600                 /* QP confirmation over RoCE fabric */
 601                 reason_code = smc_clnt_conf_first_link(smc);
 602                 if (reason_code)
 603                         return smc_connect_abort(smc, reason_code,
 604                                                  local_contact);
 605         }
 606         mutex_unlock(&smc_create_lgr_pending);
 607
 608         smc_copy_sock_settings_to_clc(smc);
 609         if (smc->sk.sk_state == SMC_INIT)
 610                 smc->sk.sk_state = SMC_ACTIVE;
 611
 612         return 0;
 613 }
 614
 615 /* setup for ISM connection of client */
 616 static int smc_connect_ism(struct smc_sock *smc,
 617                            struct smc_clc_msg_accept_confirm *aclc,
 618                            struct smcd_dev *ismdev)
 619 {
 620         int local_contact = SMC_FIRST_CONTACT;
 621         int rc = 0;
 622
 623         mutex_lock(&smc_create_lgr_pending);
 624         local_contact = smc_conn_create(smc, true, aclc->hdr.flag, NULL, 0, 0,
 625                                         NULL, ismdev, aclc->gid);
 626         if (local_contact < 0)
 627                 return smc_connect_abort(smc, SMC_CLC_DECL_MEM, 0);
 628
 629         /* Create send and receive buffers */
 630         if (smc_buf_create(smc, true))
 631                 return smc_connect_abort(smc, SMC_CLC_DECL_MEM, local_contact);
 632
 633         smc_conn_save_peer_info(smc, aclc);
 634         smc_close_init(smc);
 635         smc_rx_init(smc);
 636         smc_tx_init(smc);
 637
 638         rc = smc_clc_send_confirm(smc);
 639         if (rc)
 640                 return smc_connect_abort(smc, rc, local_contact);
 641         mutex_unlock(&smc_create_lgr_pending);
 642
 643         smc_copy_sock_settings_to_clc(smc);
 644         if (smc->sk.sk_state == SMC_INIT)
 645                 smc->sk.sk_state = SMC_ACTIVE;
 646
 647         return 0;
 648 }
 649
 650 /* perform steps before actually connecting */
 651 static int __smc_connect(struct smc_sock *smc)
 652 {
 653         bool ism_supported = false, rdma_supported = false;
 654         struct smc_clc_msg_accept_confirm aclc;
 655         struct smc_ib_device *ibdev;
 656         struct smcd_dev *ismdev;
 657         u8 gid[SMC_GID_SIZE];
 658         unsigned short vlan;
 659         int smc_type;
 660         int rc = 0;
 661         u8 ibport;
 662
 663         sock_hold(&smc->sk); /* sock put in passive closing */
 664
 665         if (smc->use_fallback)
 666                 return smc_connect_fallback(smc, smc->fallback_rsn);
 667
 668         /* if peer has not signalled SMC-capability, fall back */
 669         if (!tcp_sk(smc->clcsock->sk)->syn_smc)
 670                 return smc_connect_fallback(smc, SMC_CLC_DECL_PEERNOSMC);
 671
 672         /* IPSec connections opt out of SMC-R optimizations */
 673         if (using_ipsec(smc))
 674                 return smc_connect_decline_fallback(smc, SMC_CLC_DECL_IPSEC);
 675
 676         /* check for VLAN ID */
 677         if (smc_vlan_by_tcpsk(smc->clcsock, &vlan))
 678                 return smc_connect_decline_fallback(smc, SMC_CLC_DECL_CNFERR);
 679
 680         /* check if there is an ism device available */
 681         if (!smc_check_ism(smc, &ismdev) &&
 682             !smc_connect_ism_vlan_setup(smc, ismdev, vlan)) {
 683                 /* ISM is supported for this connection */
 684                 ism_supported = true;
 685                 smc_type = SMC_TYPE_D;
 686         }
 687
 688         /* check if there is a rdma device available */
 689         if (!smc_check_rdma(smc, &ibdev, &ibport, vlan, gid)) {
 690                 /* RDMA is supported for this connection */
 691                 rdma_supported = true;
 692                 if (ism_supported)
 693                         smc_type = SMC_TYPE_B; /* both */
 694                 else
 695                         smc_type = SMC_TYPE_R; /* only RDMA */
 696         }
 697
 698         /* if neither ISM nor RDMA are supported, fallback */
 699         if (!rdma_supported && !ism_supported)
 700                 return smc_connect_decline_fallback(smc, SMC_CLC_DECL_NOSMCDEV);
 701
 702         /* perform CLC handshake */
 703         rc = smc_connect_clc(smc, smc_type, &aclc, ibdev, ibport, gid, ismdev);
 704         if (rc) {
 705                 smc_connect_ism_vlan_cleanup(smc, ism_supported, ismdev, vlan);
 706                 return smc_connect_decline_fallback(smc, rc);
 707         }
 708
 709         /* depending on previous steps, connect using rdma or ism */
 710         if (rdma_supported && aclc.hdr.path == SMC_TYPE_R)
 711                 rc = smc_connect_rdma(smc, &aclc, ibdev, ibport);
 712         else if (ism_supported && aclc.hdr.path == SMC_TYPE_D)
 713                 rc = smc_connect_ism(smc, &aclc, ismdev);
 714         else
 715                 rc = SMC_CLC_DECL_MODEUNSUPP;
 716         if (rc) {
 717                 smc_connect_ism_vlan_cleanup(smc, ism_supported, ismdev, vlan);
 718                 return smc_connect_decline_fallback(smc, rc);
 719         }
 720
 721         smc_connect_ism_vlan_cleanup(smc, ism_supported, ismdev, vlan);
 722         return 0;
 723 }
 724
 725 static void smc_connect_work(struct work_struct *work)
 726 {
 727         struct smc_sock *smc = container_of(work, struct smc_sock,
 728                                             connect_work);
 729         int rc;
 730
 731         lock_sock(&smc->sk);
 732         rc = kernel_connect(smc->clcsock, &smc->connect_info->addr,
 733                             smc->connect_info->alen, smc->connect_info->flags);
 734         if (smc->clcsock->sk->sk_err) {
 735                 smc->sk.sk_err = smc->clcsock->sk->sk_err;
 736                 goto out;
 737         }
 738         if (rc < 0) {
 739                 smc->sk.sk_err = -rc;
 740                 goto out;
 741         }
 742
 743         rc = __smc_connect(smc);
 744         if (rc < 0)
 745                 smc->sk.sk_err = -rc;
 746
 747 out:
 748         if (smc->sk.sk_err)
 749                 smc->sk.sk_state_change(&smc->sk);
 750         else
 751                 smc->sk.sk_write_space(&smc->sk);
 752         kfree(smc->connect_info);
 753         smc->connect_info = NULL;
 754         release_sock(&smc->sk);
 755 }
 756
 757 static int smc_connect(struct socket *sock, struct sockaddr *addr,
 758                        int alen, int flags)
 759 {
 760         struct sock *sk = sock->sk;
 761         struct smc_sock *smc;
 762         int rc = -EINVAL;
 763
 764         smc = smc_sk(sk);
 765
 766         /* separate smc parameter checking to be safe */
 767         if (alen < sizeof(addr->sa_family))
 768                 goto out_err;
 769         if (addr->sa_family != AF_INET && addr->sa_family != AF_INET6)
 770                 goto out_err;
 771
 772         lock_sock(sk);
 773         switch (sk->sk_state) {
 774         default:
 775                 goto out;
 776         case SMC_ACTIVE:
 777                 rc = -EISCONN;
 778                 goto out;
 779         case SMC_INIT:
 780                 rc = 0;
 781                 break;
 782         }
 783
 784         smc_copy_sock_settings_to_clc(smc);
 785         tcp_sk(smc->clcsock->sk)->syn_smc = 1;
 786         if (flags & O_NONBLOCK) {
 787                 if (smc->connect_info) {
 788                         rc = -EALREADY;
 789                         goto out;
 790                 }
 791                 smc->connect_info = kzalloc(alen + 2 * sizeof(int), GFP_KERNEL);
 792                 if (!smc->connect_info) {
 793                         rc = -ENOMEM;
 794                         goto out;
 795                 }
 796                 smc->connect_info->alen = alen;
 797                 smc->connect_info->flags = flags ^ O_NONBLOCK;
 798                 memcpy(&smc->connect_info->addr, addr, alen);
 799                 schedule_work(&smc->connect_work);
 800                 rc = -EINPROGRESS;
 801         } else {
 802                 rc = kernel_connect(smc->clcsock, addr, alen, flags);
 803                 if (rc)
 804                         goto out;
 805
 806                 rc = __smc_connect(smc);
 807                 if (rc < 0)
 808                         goto out;
 809                 else
 810                         rc = 0; /* success cases including fallback */
 811         }
 812
 813 out:
 814         release_sock(sk);
 815 out_err:
 816         return rc;
 817 }
 818
 819 static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc)
 820 {
 821         struct socket *new_clcsock = NULL;
 822         struct sock *lsk = &lsmc->sk;
 823         struct sock *new_sk;
 824         int rc;
 825
 826         release_sock(lsk);
 827         new_sk = smc_sock_alloc(sock_net(lsk), NULL, lsk->sk_protocol);
 828         if (!new_sk) {
 829                 rc = -ENOMEM;
 830                 lsk->sk_err = ENOMEM;
 831                 *new_smc = NULL;
 832                 lock_sock(lsk);
 833                 goto out;
 834         }
 835         *new_smc = smc_sk(new_sk);
 836
 837         rc = kernel_accept(lsmc->clcsock, &new_clcsock, 0);
 838         lock_sock(lsk);
 839         if  (rc < 0)
 840                 lsk->sk_err = -rc;
 841         if (rc < 0 || lsk->sk_state == SMC_CLOSED) {
 842                 if (new_clcsock)
 843                         sock_release(new_clcsock);
 844                 new_sk->sk_state = SMC_CLOSED;
 845                 sock_set_flag(new_sk, SOCK_DEAD);
 846                 new_sk->sk_prot->unhash(new_sk);
 847                 sock_put(new_sk); /* final */
 848                 *new_smc = NULL;
 849                 goto out;
 850         }
 851
 852         (*new_smc)->clcsock = new_clcsock;
 853 out:
 854         return rc;
 855 }
 856
 857 /* add a just created sock to the accept queue of the listen sock as
 858  * candidate for a following socket accept call from user space
 859  */
 860 static void smc_accept_enqueue(struct sock *parent, struct sock *sk)
 861 {
 862         struct smc_sock *par = smc_sk(parent);
 863
 864         sock_hold(sk); /* sock_put in smc_accept_unlink () */
 865         spin_lock(&par->accept_q_lock);
 866         list_add_tail(&smc_sk(sk)->accept_q, &par->accept_q);
 867         spin_unlock(&par->accept_q_lock);
 868         sk_acceptq_added(parent);
 869 }
 870
 871 /* remove a socket from the accept queue of its parental listening socket */
 872 static void smc_accept_unlink(struct sock *sk)
 873 {
 874         struct smc_sock *par = smc_sk(sk)->listen_smc;
 875
 876         spin_lock(&par->accept_q_lock);
 877         list_del_init(&smc_sk(sk)->accept_q);
 878         spin_unlock(&par->accept_q_lock);
 879         sk_acceptq_removed(&smc_sk(sk)->listen_smc->sk);
 880         sock_put(sk); /* sock_hold in smc_accept_enqueue */
 881 }
 882
 883 /* remove a sock from the accept queue to bind it to a new socket created
 884  * for a socket accept call from user space
 885  */
 886 struct sock *smc_accept_dequeue(struct sock *parent,
 887                                 struct socket *new_sock)
 888 {
 889         struct smc_sock *isk, *n;
 890         struct sock *new_sk;
 891
 892         list_for_each_entry_safe(isk, n, &smc_sk(parent)->accept_q, accept_q) {
 893                 new_sk = (struct sock *)isk;
 894
 895                 smc_accept_unlink(new_sk);
 896                 if (new_sk->sk_state == SMC_CLOSED) {
 897                         if (isk->clcsock) {
 898                                 sock_release(isk->clcsock);
 899                                 isk->clcsock = NULL;
 900                         }
 901                         new_sk->sk_prot->unhash(new_sk);
 902                         sock_put(new_sk); /* final */
 903                         continue;
 904                 }
 905                 if (new_sock)
 906                         sock_graft(new_sk, new_sock);
 907                 return new_sk;
 908         }
 909         return NULL;
 910 }
 911
 912 /* clean up for a created but never accepted sock */
 913 void smc_close_non_accepted(struct sock *sk)
 914 {
 915         struct smc_sock *smc = smc_sk(sk);
 916
 917         lock_sock(sk);
 918         if (!sk->sk_lingertime)
 919                 /* wait for peer closing */
 920                 sk->sk_lingertime = SMC_MAX_STREAM_WAIT_TIMEOUT;
 921         if (!smc->use_fallback) {
 922                 smc_close_active(smc);
 923                 sock_set_flag(sk, SOCK_DEAD);
 924                 sk->sk_shutdown |= SHUTDOWN_MASK;
 925         }
 926         if (smc->clcsock) {
 927                 struct socket *tcp;
 928
 929                 tcp = smc->clcsock;
 930                 smc->clcsock = NULL;
 931                 sock_release(tcp);
 932         }
 933         if (smc->use_fallback) {
 934                 sock_put(sk); /* passive closing */
 935                 sk->sk_state = SMC_CLOSED;
 936         } else {
 937                 if (sk->sk_state == SMC_CLOSED)
 938                         smc_conn_free(&smc->conn);
 939         }
 940         release_sock(sk);
 941         sk->sk_prot->unhash(sk);
 942         sock_put(sk); /* final sock_put */
 943 }
 944
 945 static int smc_serv_conf_first_link(struct smc_sock *smc)
 946 {
 947         struct net *net = sock_net(smc->clcsock->sk);
 948         struct smc_link_group *lgr = smc->conn.lgr;
 949         struct smc_link *link;
 950         int rest;
 951         int rc;
 952
 953         link = &lgr->lnk[SMC_SINGLE_LINK];
 954
 955         if (smc_reg_rmb(link, smc->conn.rmb_desc, false))
 956                 return SMC_CLC_DECL_ERR_REGRMB;
 957
 958         /* send CONFIRM LINK request to client over the RoCE fabric */
 959         rc = smc_llc_send_confirm_link(link, SMC_LLC_REQ);
 960         if (rc < 0)
 961                 return SMC_CLC_DECL_TIMEOUT_CL;
 962
 963         /* receive CONFIRM LINK response from client over the RoCE fabric */
 964         rest = wait_for_completion_interruptible_timeout(
 965                 &link->llc_confirm_resp,
 966                 SMC_LLC_WAIT_FIRST_TIME);
 967         if (rest <= 0) {
 968                 struct smc_clc_msg_decline dclc;
 969
 970                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
 971                                       SMC_CLC_DECLINE);
 972                 return rc;
 973         }
 974
 975         if (link->llc_confirm_resp_rc)
 976                 return SMC_CLC_DECL_RMBE_EC;
 977
 978         /* send ADD LINK request to client over the RoCE fabric */
 979         rc = smc_llc_send_add_link(link,
 980                                    link->smcibdev->mac[link->ibport - 1],
 981                                    link->gid, SMC_LLC_REQ);
 982         if (rc < 0)
 983                 return SMC_CLC_DECL_TIMEOUT_AL;
 984
 985         /* receive ADD LINK response from client over the RoCE fabric */
 986         rest = wait_for_completion_interruptible_timeout(&link->llc_add_resp,
 987                                                          SMC_LLC_WAIT_TIME);
 988         if (rest <= 0) {
 989                 struct smc_clc_msg_decline dclc;
 990
 991                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
 992                                       SMC_CLC_DECLINE);
 993                 return rc;
 994         }
 995
 996         smc_llc_link_active(link, net->ipv4.sysctl_tcp_keepalive_time);
 997
 998         return 0;
 999 }
1000
1001 /* listen worker: finish */
1002 static void smc_listen_out(struct smc_sock *new_smc)
1003 {
1004         struct smc_sock *lsmc = new_smc->listen_smc;
1005         struct sock *newsmcsk = &new_smc->sk;
1006
1007         lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING);
1008         if (lsmc->sk.sk_state == SMC_LISTEN) {
1009                 smc_accept_enqueue(&lsmc->sk, newsmcsk);
1010         } else { /* no longer listening */
1011                 smc_close_non_accepted(newsmcsk);
1012         }
1013         release_sock(&lsmc->sk);
1014
1015         /* Wake up accept */
1016         lsmc->sk.sk_data_ready(&lsmc->sk);
1017         sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */
1018 }
1019
1020 /* listen worker: finish in state connected */
1021 static void smc_listen_out_connected(struct smc_sock *new_smc)
1022 {
1023         struct sock *newsmcsk = &new_smc->sk;
1024
1025         sk_refcnt_debug_inc(newsmcsk);
1026         if (newsmcsk->sk_state == SMC_INIT)
1027                 newsmcsk->sk_state = SMC_ACTIVE;
1028
1029         smc_listen_out(new_smc);
1030 }
1031
1032 /* listen worker: finish in error state */
1033 static void smc_listen_out_err(struct smc_sock *new_smc)
1034 {
1035         struct sock *newsmcsk = &new_smc->sk;
1036
1037         if (newsmcsk->sk_state == SMC_INIT)
1038                 sock_put(&new_smc->sk); /* passive closing */
1039         newsmcsk->sk_state = SMC_CLOSED;
1040         smc_conn_free(&new_smc->conn);
1041
1042         smc_listen_out(new_smc);
1043 }
1044
1045 /* listen worker: decline and fall back if possible */
1046 static void smc_listen_decline(struct smc_sock *new_smc, int reason_code,
1047                                int local_contact)
1048 {
1049         /* RDMA setup failed, switch back to TCP */
1050         if (local_contact == SMC_FIRST_CONTACT)
1051                 smc_lgr_forget(new_smc->conn.lgr);
1052         if (reason_code < 0) { /* error, no fallback possible */
1053                 smc_listen_out_err(new_smc);
1054                 return;
1055         }
1056         smc_conn_free(&new_smc->conn);
1057         new_smc->use_fallback = true;
1058         new_smc->fallback_rsn = reason_code;
1059         if (reason_code && reason_code != SMC_CLC_DECL_PEERDECL) {
1060                 if (smc_clc_send_decline(new_smc, reason_code) < 0) {
1061                         smc_listen_out_err(new_smc);
1062                         return;
1063                 }
1064         }
1065         smc_listen_out_connected(new_smc);
1066 }
1067
1068 /* listen worker: check prefixes */
1069 static int smc_listen_rdma_check(struct smc_sock *new_smc,
1070                                  struct smc_clc_msg_proposal *pclc)
1071 {
1072         struct smc_clc_msg_proposal_prefix *pclc_prfx;
1073         struct socket *newclcsock = new_smc->clcsock;
1074
1075         pclc_prfx = smc_clc_proposal_get_prefix(pclc);
1076         if (smc_clc_prfx_match(newclcsock, pclc_prfx))
1077                 return SMC_CLC_DECL_CNFERR;
1078
1079         return 0;
1080 }
1081
1082 /* listen worker: initialize connection and buffers */
1083 static int smc_listen_rdma_init(struct smc_sock *new_smc,
1084                                 struct smc_clc_msg_proposal *pclc,
1085                                 struct smc_ib_device *ibdev, u8 ibport,
1086                                 int *local_contact)
1087 {
1088         /* allocate connection / link group */
1089         *local_contact = smc_conn_create(new_smc, false, 0, ibdev, ibport, 0,
1090                                          &pclc->lcl, NULL, 0);
1091         if (*local_contact < 0) {
1092                 if (*local_contact == -ENOMEM)
1093                         return SMC_CLC_DECL_MEM;/* insufficient memory*/
1094                 return SMC_CLC_DECL_INTERR; /* other error */
1095         }
1096
1097         /* create send buffer and rmb */
1098         if (smc_buf_create(new_smc, false))
1099                 return SMC_CLC_DECL_MEM;
1100
1101         return 0;
1102 }
1103
1104 /* listen worker: initialize connection and buffers for SMC-D */
1105 static int smc_listen_ism_init(struct smc_sock *new_smc,
1106                                struct smc_clc_msg_proposal *pclc,
1107                                struct smcd_dev *ismdev,
1108                                int *local_contact)
1109 {
1110         struct smc_clc_msg_smcd *pclc_smcd;
1111
1112         pclc_smcd = smc_get_clc_msg_smcd(pclc);
1113         *local_contact = smc_conn_create(new_smc, true, 0, NULL, 0, 0, NULL,
1114                                          ismdev, pclc_smcd->gid);
1115         if (*local_contact < 0) {
1116                 if (*local_contact == -ENOMEM)
1117                         return SMC_CLC_DECL_MEM;/* insufficient memory*/
1118                 return SMC_CLC_DECL_INTERR; /* other error */
1119         }
1120
1121         /* Check if peer can be reached via ISM device */
1122         if (smc_ism_cantalk(new_smc->conn.lgr->peer_gid,
1123                             new_smc->conn.lgr->vlan_id,
1124                             new_smc->conn.lgr->smcd)) {
1125                 if (*local_contact == SMC_FIRST_CONTACT)
1126                         smc_lgr_forget(new_smc->conn.lgr);
1127                 smc_conn_free(&new_smc->conn);
1128                 return SMC_CLC_DECL_CNFERR;
1129         }
1130
1131         /* Create send and receive buffers */
1132         if (smc_buf_create(new_smc, true)) {
1133                 if (*local_contact == SMC_FIRST_CONTACT)
1134                         smc_lgr_forget(new_smc->conn.lgr);
1135                 smc_conn_free(&new_smc->conn);
1136                 return SMC_CLC_DECL_MEM;
1137         }
1138
1139         return 0;
1140 }
1141
1142 /* listen worker: register buffers */
1143 static int smc_listen_rdma_reg(struct smc_sock *new_smc, int local_contact)
1144 {
1145         struct smc_link *link = &new_smc->conn.lgr->lnk[SMC_SINGLE_LINK];
1146
1147         if (local_contact != SMC_FIRST_CONTACT) {
1148                 if (!new_smc->conn.rmb_desc->reused) {
1149                         if (smc_reg_rmb(link, new_smc->conn.rmb_desc, true))
1150                                 return SMC_CLC_DECL_ERR_REGRMB;
1151                 }
1152         }
1153         smc_rmb_sync_sg_for_device(&new_smc->conn);
1154
1155         return 0;
1156 }
1157
1158 /* listen worker: finish RDMA setup */
1159 static int smc_listen_rdma_finish(struct smc_sock *new_smc,
1160                                   struct smc_clc_msg_accept_confirm *cclc,
1161                                   int local_contact)
1162 {
1163         struct smc_link *link = &new_smc->conn.lgr->lnk[SMC_SINGLE_LINK];
1164         int reason_code = 0;
1165
1166         if (local_contact == SMC_FIRST_CONTACT)
1167                 smc_link_save_peer_info(link, cclc);
1168
1169         if (smc_rmb_rtoken_handling(&new_smc->conn, cclc)) {
1170                 reason_code = SMC_CLC_DECL_ERR_RTOK;
1171                 goto decline;
1172         }
1173
1174         if (local_contact == SMC_FIRST_CONTACT) {
1175                 if (smc_ib_ready_link(link)) {
1176                         reason_code = SMC_CLC_DECL_ERR_RDYLNK;
1177                         goto decline;
1178                 }
1179                 /* QP confirmation over RoCE fabric */
1180                 reason_code = smc_serv_conf_first_link(new_smc);
1181                 if (reason_code)
1182                         goto decline;
1183         }
1184         return 0;
1185
1186 decline:
1187         mutex_unlock(&smc_create_lgr_pending);
1188         smc_listen_decline(new_smc, reason_code, local_contact);
1189         return reason_code;
1190 }
1191
1192 /* setup for RDMA connection of server */
1193 static void smc_listen_work(struct work_struct *work)
1194 {
1195         struct smc_sock *new_smc = container_of(work, struct smc_sock,
1196                                                 smc_listen_work);
1197         struct socket *newclcsock = new_smc->clcsock;
1198         struct smc_clc_msg_accept_confirm cclc;
1199         struct smc_clc_msg_proposal *pclc;
1200         struct smc_ib_device *ibdev;
1201         bool ism_supported = false;
1202         struct smcd_dev *ismdev;
1203         u8 buf[SMC_CLC_MAX_LEN];
1204         int local_contact = 0;
1205         unsigned short vlan;
1206         int reason_code = 0;
1207         int rc = 0;
1208         u8 ibport;
1209
1210         if (new_smc->use_fallback) {
1211                 smc_listen_out_connected(new_smc);
1212                 return;
1213         }
1214
1215         /* check if peer is smc capable */
1216         if (!tcp_sk(newclcsock->sk)->syn_smc) {
1217                 new_smc->use_fallback = true;
1218                 new_smc->fallback_rsn = SMC_CLC_DECL_PEERNOSMC;
1219                 smc_listen_out_connected(new_smc);
1220                 return;
1221         }
1222
1223         /* do inband token exchange -
1224          * wait for and receive SMC Proposal CLC message
1225          */
1226         pclc = (struct smc_clc_msg_proposal *)&buf;
1227         reason_code = smc_clc_wait_msg(new_smc, pclc, SMC_CLC_MAX_LEN,
1228                                        SMC_CLC_PROPOSAL);
1229         if (reason_code) {
1230                 smc_listen_decline(new_smc, reason_code, 0);
1231                 return;
1232         }
1233
1234         /* IPSec connections opt out of SMC-R optimizations */
1235         if (using_ipsec(new_smc)) {
1236                 smc_listen_decline(new_smc, SMC_CLC_DECL_IPSEC, 0);
1237                 return;
1238         }
1239
1240         mutex_lock(&smc_create_lgr_pending);
1241         smc_close_init(new_smc);
1242         smc_rx_init(new_smc);
1243         smc_tx_init(new_smc);
1244
1245         /* check if ISM is available */
1246         if ((pclc->hdr.path == SMC_TYPE_D || pclc->hdr.path == SMC_TYPE_B) &&
1247             !smc_check_ism(new_smc, &ismdev) &&
1248             !smc_listen_ism_init(new_smc, pclc, ismdev, &local_contact)) {
1249                 ism_supported = true;
1250         }
1251
1252         /* check if RDMA is available */
1253         if (!ism_supported &&
1254             ((pclc->hdr.path != SMC_TYPE_R && pclc->hdr.path != SMC_TYPE_B) ||
1255              smc_vlan_by_tcpsk(new_smc->clcsock, &vlan) ||
1256              smc_check_rdma(new_smc, &ibdev, &ibport, vlan, NULL) ||
1257              smc_listen_rdma_check(new_smc, pclc) ||
1258              smc_listen_rdma_init(new_smc, pclc, ibdev, ibport,
1259                                   &local_contact) ||
1260              smc_listen_rdma_reg(new_smc, local_contact))) {
1261                 /* SMC not supported, decline */
1262                 mutex_unlock(&smc_create_lgr_pending);
1263                 smc_listen_decline(new_smc, SMC_CLC_DECL_MODEUNSUPP,
1264                                    local_contact);
1265                 return;
1266         }
1267
1268         /* send SMC Accept CLC message */
1269         rc = smc_clc_send_accept(new_smc, local_contact);
1270         if (rc) {
1271                 mutex_unlock(&smc_create_lgr_pending);
1272                 smc_listen_decline(new_smc, rc, local_contact);
1273                 return;
1274         }
1275
1276         /* receive SMC Confirm CLC message */
1277         reason_code = smc_clc_wait_msg(new_smc, &cclc, sizeof(cclc),
1278                                        SMC_CLC_CONFIRM);
1279         if (reason_code) {
1280                 mutex_unlock(&smc_create_lgr_pending);
1281                 smc_listen_decline(new_smc, reason_code, local_contact);
1282                 return;
1283         }
1284
1285         /* finish worker */
1286         if (!ism_supported) {
1287                 if (smc_listen_rdma_finish(new_smc, &cclc, local_contact))
1288                         return;
1289         }
1290         smc_conn_save_peer_info(new_smc, &cclc);
1291         mutex_unlock(&smc_create_lgr_pending);
1292         smc_listen_out_connected(new_smc);
1293 }
1294
1295 static void smc_tcp_listen_work(struct work_struct *work)
1296 {
1297         struct smc_sock *lsmc = container_of(work, struct smc_sock,
1298                                              tcp_listen_work);
1299         struct sock *lsk = &lsmc->sk;
1300         struct smc_sock *new_smc;
1301         int rc = 0;
1302
1303         lock_sock(lsk);
1304         while (lsk->sk_state == SMC_LISTEN) {
1305                 rc = smc_clcsock_accept(lsmc, &new_smc);
1306                 if (rc)
1307                         goto out;
1308                 if (!new_smc)
1309                         continue;
1310
1311                 new_smc->listen_smc = lsmc;
1312                 new_smc->use_fallback = lsmc->use_fallback;
1313                 new_smc->fallback_rsn = lsmc->fallback_rsn;
1314                 sock_hold(lsk); /* sock_put in smc_listen_work */
1315                 INIT_WORK(&new_smc->smc_listen_work, smc_listen_work);
1316                 smc_copy_sock_settings_to_smc(new_smc);
1317                 new_smc->sk.sk_sndbuf = lsmc->sk.sk_sndbuf;
1318                 new_smc->sk.sk_rcvbuf = lsmc->sk.sk_rcvbuf;
1319                 sock_hold(&new_smc->sk); /* sock_put in passive closing */
1320                 if (!schedule_work(&new_smc->smc_listen_work))
1321                         sock_put(&new_smc->sk);
1322         }
1323
1324 out:
1325         release_sock(lsk);
1326         sock_put(&lsmc->sk); /* sock_hold in smc_listen */
1327 }
1328
1329 static int smc_listen(struct socket *sock, int backlog)
1330 {
1331         struct sock *sk = sock->sk;
1332         struct smc_sock *smc;
1333         int rc;
1334
1335         smc = smc_sk(sk);
1336         lock_sock(sk);
1337
1338         rc = -EINVAL;
1339         if ((sk->sk_state != SMC_INIT) && (sk->sk_state != SMC_LISTEN))
1340                 goto out;
1341
1342         rc = 0;
1343         if (sk->sk_state == SMC_LISTEN) {
1344                 sk->sk_max_ack_backlog = backlog;
1345                 goto out;
1346         }
1347         /* some socket options are handled in core, so we could not apply
1348          * them to the clc socket -- copy smc socket options to clc socket
1349          */
1350         smc_copy_sock_settings_to_clc(smc);
1351         if (!smc->use_fallback)
1352                 tcp_sk(smc->clcsock->sk)->syn_smc = 1;
1353
1354         rc = kernel_listen(smc->clcsock, backlog);
1355         if (rc)
1356                 goto out;
1357         sk->sk_max_ack_backlog = backlog;
1358         sk->sk_ack_backlog = 0;
1359         sk->sk_state = SMC_LISTEN;
1360         INIT_WORK(&smc->tcp_listen_work, smc_tcp_listen_work);
1361         sock_hold(sk); /* sock_hold in tcp_listen_worker */
1362         if (!schedule_work(&smc->tcp_listen_work))
1363                 sock_put(sk);
1364
1365 out:
1366         release_sock(sk);
1367         return rc;
1368 }
1369
1370 static int smc_accept(struct socket *sock, struct socket *new_sock,
1371                       int flags, bool kern)
1372 {
1373         struct sock *sk = sock->sk, *nsk;
1374         DECLARE_WAITQUEUE(wait, current);
1375         struct smc_sock *lsmc;
1376         long timeo;
1377         int rc = 0;
1378
1379         lsmc = smc_sk(sk);
1380         sock_hold(sk); /* sock_put below */
1381         lock_sock(sk);
1382
1383         if (lsmc->sk.sk_state != SMC_LISTEN) {
1384                 rc = -EINVAL;
1385                 release_sock(sk);
1386                 goto out;
1387         }
1388
1389         /* Wait for an incoming connection */
1390         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
1391         add_wait_queue_exclusive(sk_sleep(sk), &wait);
1392         while (!(nsk = smc_accept_dequeue(sk, new_sock))) {
1393                 set_current_state(TASK_INTERRUPTIBLE);
1394                 if (!timeo) {
1395                         rc = -EAGAIN;
1396                         break;
1397                 }
1398                 release_sock(sk);
1399                 timeo = schedule_timeout(timeo);
1400                 /* wakeup by sk_data_ready in smc_listen_work() */
1401                 sched_annotate_sleep();
1402                 lock_sock(sk);
1403                 if (signal_pending(current)) {
1404                         rc = sock_intr_errno(timeo);
1405                         break;
1406                 }
1407         }
1408         set_current_state(TASK_RUNNING);
1409         remove_wait_queue(sk_sleep(sk), &wait);
1410
1411         if (!rc)
1412                 rc = sock_error(nsk);
1413         release_sock(sk);
1414         if (rc)
1415                 goto out;
1416
1417         if (lsmc->sockopt_defer_accept && !(flags & O_NONBLOCK)) {
1418                 /* wait till data arrives on the socket */
1419                 timeo = msecs_to_jiffies(lsmc->sockopt_defer_accept *
1420                                                                 MSEC_PER_SEC);
1421                 if (smc_sk(nsk)->use_fallback) {
1422                         struct sock *clcsk = smc_sk(nsk)->clcsock->sk;
1423
1424                         lock_sock(clcsk);
1425                         if (skb_queue_empty(&clcsk->sk_receive_queue))
1426                                 sk_wait_data(clcsk, &timeo, NULL);
1427                         release_sock(clcsk);
1428                 } else if (!atomic_read(&smc_sk(nsk)->conn.bytes_to_rcv)) {
1429                         lock_sock(nsk);
1430                         smc_rx_wait(smc_sk(nsk), &timeo, smc_rx_data_available);
1431                         release_sock(nsk);
1432                 }
1433         }
1434
1435 out:
1436         sock_put(sk); /* sock_hold above */
1437         return rc;
1438 }
1439
1440 static int smc_getname(struct socket *sock, struct sockaddr *addr,
1441                        int peer)
1442 {
1443         struct smc_sock *smc;
1444
1445         if (peer && (sock->sk->sk_state != SMC_ACTIVE) &&
1446             (sock->sk->sk_state != SMC_APPCLOSEWAIT1))
1447                 return -ENOTCONN;
1448
1449         smc = smc_sk(sock->sk);
1450
1451         return smc->clcsock->ops->getname(smc->clcsock, addr, peer);
1452 }
1453
1454 static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1455 {
1456         struct sock *sk = sock->sk;
1457         struct smc_sock *smc;
1458         int rc = -EPIPE;
1459
1460         smc = smc_sk(sk);
1461         lock_sock(sk);
1462         if ((sk->sk_state != SMC_ACTIVE) &&
1463             (sk->sk_state != SMC_APPCLOSEWAIT1) &&
1464             (sk->sk_state != SMC_INIT))
1465                 goto out;
1466
1467         if (msg->msg_flags & MSG_FASTOPEN) {
1468                 if (sk->sk_state == SMC_INIT) {
1469                         smc->use_fallback = true;
1470                         smc->fallback_rsn = SMC_CLC_DECL_OPTUNSUPP;
1471                 } else {
1472                         rc = -EINVAL;
1473                         goto out;
1474                 }
1475         }
1476
1477         if (smc->use_fallback)
1478                 rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len);
1479         else
1480                 rc = smc_tx_sendmsg(smc, msg, len);
1481 out:
1482         release_sock(sk);
1483         return rc;
1484 }
1485
1486 static int smc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
1487                        int flags)
1488 {
1489         struct sock *sk = sock->sk;
1490         struct smc_sock *smc;
1491         int rc = -ENOTCONN;
1492
1493         smc = smc_sk(sk);
1494         lock_sock(sk);
1495         if ((sk->sk_state == SMC_INIT) ||
1496             (sk->sk_state == SMC_LISTEN) ||
1497             (sk->sk_state == SMC_CLOSED))
1498                 goto out;
1499
1500         if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
1501                 rc = 0;
1502                 goto out;
1503         }
1504
1505         if (smc->use_fallback) {
1506                 rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags);
1507         } else {
1508                 msg->msg_namelen = 0;
1509                 rc = smc_rx_recvmsg(smc, msg, NULL, len, flags);
1510         }
1511
1512 out:
1513         release_sock(sk);
1514         return rc;
1515 }
1516
1517 static __poll_t smc_accept_poll(struct sock *parent)
1518 {
1519         struct smc_sock *isk = smc_sk(parent);
1520         __poll_t mask = 0;
1521
1522         spin_lock(&isk->accept_q_lock);
1523         if (!list_empty(&isk->accept_q))
1524                 mask = EPOLLIN | EPOLLRDNORM;
1525         spin_unlock(&isk->accept_q_lock);
1526
1527         return mask;
1528 }
1529
1530 static __poll_t smc_poll(struct file *file, struct socket *sock,
1531                              poll_table *wait)
1532 {
1533         struct sock *sk = sock->sk;
1534         __poll_t mask = 0;
1535         struct smc_sock *smc;
1536
1537         if (!sk)
1538                 return EPOLLNVAL;
1539
1540         smc = smc_sk(sock->sk);
1541         if (smc->use_fallback) {
1542                 /* delegate to CLC child sock */
1543                 mask = smc->clcsock->ops->poll(file, smc->clcsock, wait);
1544                 sk->sk_err = smc->clcsock->sk->sk_err;
1545                 if (sk->sk_err)
1546                         mask |= EPOLLERR;
1547         } else {
1548                 if (sk->sk_state != SMC_CLOSED)
1549                         sock_poll_wait(file, sock, wait);
1550                 if (sk->sk_err)
1551                         mask |= EPOLLERR;
1552                 if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
1553                     (sk->sk_state == SMC_CLOSED))
1554                         mask |= EPOLLHUP;
1555                 if (sk->sk_state == SMC_LISTEN) {
1556                         /* woken up by sk_data_ready in smc_listen_work() */
1557                         mask = smc_accept_poll(sk);
1558                 } else {
1559                         if (atomic_read(&smc->conn.sndbuf_space) ||
1560                             sk->sk_shutdown & SEND_SHUTDOWN) {
1561                                 mask |= EPOLLOUT | EPOLLWRNORM;
1562                         } else {
1563                                 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1564                                 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1565                         }
1566                         if (atomic_read(&smc->conn.bytes_to_rcv))
1567                                 mask |= EPOLLIN | EPOLLRDNORM;
1568                         if (sk->sk_shutdown & RCV_SHUTDOWN)
1569                                 mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
1570                         if (sk->sk_state == SMC_APPCLOSEWAIT1)
1571                                 mask |= EPOLLIN;
1572                         if (smc->conn.urg_state == SMC_URG_VALID)
1573                                 mask |= EPOLLPRI;
1574                 }
1575         }
1576
1577         return mask;
1578 }
1579
1580 static int smc_shutdown(struct socket *sock, int how)
1581 {
1582         struct sock *sk = sock->sk;
1583         struct smc_sock *smc;
1584         int rc = -EINVAL;
1585         int rc1 = 0;
1586
1587         smc = smc_sk(sk);
1588
1589         if ((how < SHUT_RD) || (how > SHUT_RDWR))
1590                 return rc;
1591
1592         lock_sock(sk);
1593
1594         rc = -ENOTCONN;
1595         if ((sk->sk_state != SMC_ACTIVE) &&
1596             (sk->sk_state != SMC_PEERCLOSEWAIT1) &&
1597             (sk->sk_state != SMC_PEERCLOSEWAIT2) &&
1598             (sk->sk_state != SMC_APPCLOSEWAIT1) &&
1599             (sk->sk_state != SMC_APPCLOSEWAIT2) &&
1600             (sk->sk_state != SMC_APPFINCLOSEWAIT))
1601                 goto out;
1602         if (smc->use_fallback) {
1603                 rc = kernel_sock_shutdown(smc->clcsock, how);
1604                 sk->sk_shutdown = smc->clcsock->sk->sk_shutdown;
1605                 if (sk->sk_shutdown == SHUTDOWN_MASK)
1606                         sk->sk_state = SMC_CLOSED;
1607                 goto out;
1608         }
1609         switch (how) {
1610         case SHUT_RDWR:         /* shutdown in both directions */
1611                 rc = smc_close_active(smc);
1612                 break;
1613         case SHUT_WR:
1614                 rc = smc_close_shutdown_write(smc);
1615                 break;
1616         case SHUT_RD:
1617                 rc = 0;
1618                 /* nothing more to do because peer is not involved */
1619                 break;
1620         }
1621         if (smc->clcsock)
1622                 rc1 = kernel_sock_shutdown(smc->clcsock, how);
1623         /* map sock_shutdown_cmd constants to sk_shutdown value range */
1624         sk->sk_shutdown |= how + 1;
1625
1626 out:
1627         release_sock(sk);
1628         return rc ? rc : rc1;
1629 }
1630
1631 static int smc_setsockopt(struct socket *sock, int level, int optname,
1632                           char __user *optval, unsigned int optlen)
1633 {
1634         struct sock *sk = sock->sk;
1635         struct smc_sock *smc;
1636         int val, rc;
1637
1638         smc = smc_sk(sk);
1639
1640         /* generic setsockopts reaching us here always apply to the
1641          * CLC socket
1642          */
1643         rc = smc->clcsock->ops->setsockopt(smc->clcsock, level, optname,
1644                                            optval, optlen);
1645         if (smc->clcsock->sk->sk_err) {
1646                 sk->sk_err = smc->clcsock->sk->sk_err;
1647                 sk->sk_error_report(sk);
1648         }
1649         if (rc)
1650                 return rc;
1651
1652         if (optlen < sizeof(int))
1653                 return -EINVAL;
1654         if (get_user(val, (int __user *)optval))
1655                 return -EFAULT;
1656
1657         lock_sock(sk);
1658         switch (optname) {
1659         case TCP_ULP:
1660         case TCP_FASTOPEN:
1661         case TCP_FASTOPEN_CONNECT:
1662         case TCP_FASTOPEN_KEY:
1663         case TCP_FASTOPEN_NO_COOKIE:
1664                 /* option not supported by SMC */
1665                 if (sk->sk_state == SMC_INIT) {
1666                         smc->use_fallback = true;
1667                         smc->fallback_rsn = SMC_CLC_DECL_OPTUNSUPP;
1668                 } else {
1669                         if (!smc->use_fallback)
1670                                 rc = -EINVAL;
1671                 }
1672                 break;
1673         case TCP_NODELAY:
1674                 if (sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) {
1675                         if (val && !smc->use_fallback)
1676                                 mod_delayed_work(system_wq, &smc->conn.tx_work,
1677                                                  0);
1678                 }
1679                 break;
1680         case TCP_CORK:
1681                 if (sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) {
1682                         if (!val && !smc->use_fallback)
1683                                 mod_delayed_work(system_wq, &smc->conn.tx_work,
1684                                                  0);
1685                 }
1686                 break;
1687         case TCP_DEFER_ACCEPT:
1688                 smc->sockopt_defer_accept = val;
1689                 break;
1690         default:
1691                 break;
1692         }
1693         release_sock(sk);
1694
1695         return rc;
1696 }
1697
1698 static int smc_getsockopt(struct socket *sock, int level, int optname,
1699                           char __user *optval, int __user *optlen)
1700 {
1701         struct smc_sock *smc;
1702
1703         smc = smc_sk(sock->sk);
1704         /* socket options apply to the CLC socket */
1705         return smc->clcsock->ops->getsockopt(smc->clcsock, level, optname,
1706                                              optval, optlen);
1707 }
1708
1709 static int smc_ioctl(struct socket *sock, unsigned int cmd,
1710                      unsigned long arg)
1711 {
1712         union smc_host_cursor cons, urg;
1713         struct smc_connection *conn;
1714         struct smc_sock *smc;
1715         int answ;
1716
1717         smc = smc_sk(sock->sk);
1718         conn = &smc->conn;
1719         lock_sock(&smc->sk);
1720         if (smc->use_fallback) {
1721                 if (!smc->clcsock) {
1722                         release_sock(&smc->sk);
1723                         return -EBADF;
1724                 }
1725                 answ = smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg);
1726                 release_sock(&smc->sk);
1727                 return answ;
1728         }
1729         switch (cmd) {
1730         case SIOCINQ: /* same as FIONREAD */
1731                 if (smc->sk.sk_state == SMC_LISTEN) {
1732                         release_sock(&smc->sk);
1733                         return -EINVAL;
1734                 }
1735                 if (smc->sk.sk_state == SMC_INIT ||
1736                     smc->sk.sk_state == SMC_CLOSED)
1737                         answ = 0;
1738                 else
1739                         answ = atomic_read(&smc->conn.bytes_to_rcv);
1740                 break;
1741         case SIOCOUTQ:
1742                 /* output queue size (not send + not acked) */
1743                 if (smc->sk.sk_state == SMC_LISTEN) {
1744                         release_sock(&smc->sk);
1745                         return -EINVAL;
1746                 }
1747                 if (smc->sk.sk_state == SMC_INIT ||
1748                     smc->sk.sk_state == SMC_CLOSED)
1749                         answ = 0;
1750                 else
1751                         answ = smc->conn.sndbuf_desc->len -
1752                                         atomic_read(&smc->conn.sndbuf_space);
1753                 break;
1754         case SIOCOUTQNSD:
1755                 /* output queue size (not send only) */
1756                 if (smc->sk.sk_state == SMC_LISTEN) {
1757                         release_sock(&smc->sk);
1758                         return -EINVAL;
1759                 }
1760                 if (smc->sk.sk_state == SMC_INIT ||
1761                     smc->sk.sk_state == SMC_CLOSED)
1762                         answ = 0;
1763                 else
1764                         answ = smc_tx_prepared_sends(&smc->conn);
1765                 break;
1766         case SIOCATMARK:
1767                 if (smc->sk.sk_state == SMC_LISTEN) {
1768                         release_sock(&smc->sk);
1769                         return -EINVAL;
1770                 }
1771                 if (smc->sk.sk_state == SMC_INIT ||
1772                     smc->sk.sk_state == SMC_CLOSED) {
1773                         answ = 0;
1774                 } else {
1775                         smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
1776                         smc_curs_copy(&urg, &conn->urg_curs, conn);
1777                         answ = smc_curs_diff(conn->rmb_desc->len,
1778                                              &cons, &urg) == 1;
1779                 }
1780                 break;
1781         default:
1782                 release_sock(&smc->sk);
1783                 return -ENOIOCTLCMD;
1784         }
1785         release_sock(&smc->sk);
1786
1787         return put_user(answ, (int __user *)arg);
1788 }
1789
1790 static ssize_t smc_sendpage(struct socket *sock, struct page *page,
1791                             int offset, size_t size, int flags)
1792 {
1793         struct sock *sk = sock->sk;
1794         struct smc_sock *smc;
1795         int rc = -EPIPE;
1796
1797         smc = smc_sk(sk);
1798         lock_sock(sk);
1799         if (sk->sk_state != SMC_ACTIVE) {
1800                 release_sock(sk);
1801                 goto out;
1802         }
1803         release_sock(sk);
1804         if (smc->use_fallback)
1805                 rc = kernel_sendpage(smc->clcsock, page, offset,
1806                                      size, flags);
1807         else
1808                 rc = sock_no_sendpage(sock, page, offset, size, flags);
1809
1810 out:
1811         return rc;
1812 }
1813
1814 /* Map the affected portions of the rmbe into an spd, note the number of bytes
1815  * to splice in conn->splice_pending, and press 'go'. Delays consumer cursor
1816  * updates till whenever a respective page has been fully processed.
1817  * Note that subsequent recv() calls have to wait till all splice() processing
1818  * completed.
1819  */
1820 static ssize_t smc_splice_read(struct socket *sock, loff_t *ppos,
1821                                struct pipe_inode_info *pipe, size_t len,
1822                                unsigned int flags)
1823 {
1824         struct sock *sk = sock->sk;
1825         struct smc_sock *smc;
1826         int rc = -ENOTCONN;
1827
1828         smc = smc_sk(sk);
1829         lock_sock(sk);
1830
1831         if (sk->sk_state == SMC_INIT ||
1832             sk->sk_state == SMC_LISTEN ||
1833             sk->sk_state == SMC_CLOSED)
1834                 goto out;
1835
1836         if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
1837                 rc = 0;
1838                 goto out;
1839         }
1840
1841         if (smc->use_fallback) {
1842                 rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos,
1843                                                     pipe, len, flags);
1844         } else {
1845                 if (*ppos) {
1846                         rc = -ESPIPE;
1847                         goto out;
1848                 }
1849                 if (flags & SPLICE_F_NONBLOCK)
1850                         flags = MSG_DONTWAIT;
1851                 else
1852                         flags = 0;
1853                 rc = smc_rx_recvmsg(smc, NULL, pipe, len, flags);
1854         }
1855 out:
1856         release_sock(sk);
1857
1858         return rc;
1859 }
1860
1861 /* must look like tcp */
1862 static const struct proto_ops smc_sock_ops = {
1863         .family         = PF_SMC,
1864         .owner          = THIS_MODULE,
1865         .release        = smc_release,
1866         .bind           = smc_bind,
1867         .connect        = smc_connect,
1868         .socketpair     = sock_no_socketpair,
1869         .accept         = smc_accept,
1870         .getname        = smc_getname,
1871         .poll           = smc_poll,
1872         .ioctl          = smc_ioctl,
1873         .listen         = smc_listen,
1874         .shutdown       = smc_shutdown,
1875         .setsockopt     = smc_setsockopt,
1876         .getsockopt     = smc_getsockopt,
1877         .sendmsg        = smc_sendmsg,
1878         .recvmsg        = smc_recvmsg,
1879         .mmap           = sock_no_mmap,
1880         .sendpage       = smc_sendpage,
1881         .splice_read    = smc_splice_read,
1882 };
1883
1884 static int smc_create(struct net *net, struct socket *sock, int protocol,
1885                       int kern)
1886 {
1887         int family = (protocol == SMCPROTO_SMC6) ? PF_INET6 : PF_INET;
1888         struct smc_sock *smc;
1889         struct sock *sk;
1890         int rc;
1891
1892         rc = -ESOCKTNOSUPPORT;
1893         if (sock->type != SOCK_STREAM)
1894                 goto out;
1895
1896         rc = -EPROTONOSUPPORT;
1897         if (protocol != SMCPROTO_SMC && protocol != SMCPROTO_SMC6)
1898                 goto out;
1899
1900         rc = -ENOBUFS;
1901         sock->ops = &smc_sock_ops;
1902         sk = smc_sock_alloc(net, sock, protocol);
1903         if (!sk)
1904                 goto out;
1905
1906         /* create internal TCP socket for CLC handshake and fallback */
1907         smc = smc_sk(sk);
1908         smc->use_fallback = false; /* assume rdma capability first */
1909         smc->fallback_rsn = 0;
1910         rc = sock_create_kern(net, family, SOCK_STREAM, IPPROTO_TCP,
1911                               &smc->clcsock);
1912         if (rc) {
1913                 sk_common_release(sk);
1914                 goto out;
1915         }
1916         smc->sk.sk_sndbuf = max(smc->clcsock->sk->sk_sndbuf, SMC_BUF_MIN_SIZE);
1917         smc->sk.sk_rcvbuf = max(smc->clcsock->sk->sk_rcvbuf, SMC_BUF_MIN_SIZE);
1918
1919 out:
1920         return rc;
1921 }
1922
1923 static const struct net_proto_family smc_sock_family_ops = {
1924         .family = PF_SMC,
1925         .owner  = THIS_MODULE,
1926         .create = smc_create,
1927 };
1928
1929 static int __init smc_init(void)
1930 {
1931         int rc;
1932
1933         rc = smc_pnet_init();
1934         if (rc)
1935                 return rc;
1936
1937         rc = smc_llc_init();
1938         if (rc) {
1939                 pr_err("%s: smc_llc_init fails with %d\n", __func__, rc);
1940                 goto out_pnet;
1941         }
1942
1943         rc = smc_cdc_init();
1944         if (rc) {
1945                 pr_err("%s: smc_cdc_init fails with %d\n", __func__, rc);
1946                 goto out_pnet;
1947         }
1948
1949         rc = proto_register(&smc_proto, 1);
1950         if (rc) {
1951                 pr_err("%s: proto_register(v4) fails with %d\n", __func__, rc);
1952                 goto out_pnet;
1953         }
1954
1955         rc = proto_register(&smc_proto6, 1);
1956         if (rc) {
1957                 pr_err("%s: proto_register(v6) fails with %d\n", __func__, rc);
1958                 goto out_proto;
1959         }
1960
1961         rc = sock_register(&smc_sock_family_ops);
1962         if (rc) {
1963                 pr_err("%s: sock_register fails with %d\n", __func__, rc);
1964                 goto out_proto6;
1965         }
1966         INIT_HLIST_HEAD(&smc_v4_hashinfo.ht);
1967         INIT_HLIST_HEAD(&smc_v6_hashinfo.ht);
1968
1969         rc = smc_ib_register_client();
1970         if (rc) {
1971                 pr_err("%s: ib_register fails with %d\n", __func__, rc);
1972                 goto out_sock;
1973         }
1974
1975         static_branch_enable(&tcp_have_smc);
1976         return 0;
1977
1978 out_sock:
1979         sock_unregister(PF_SMC);
1980 out_proto6:
1981         proto_unregister(&smc_proto6);
1982 out_proto:
1983         proto_unregister(&smc_proto);
1984 out_pnet:
1985         smc_pnet_exit();
1986         return rc;
1987 }
1988
1989 static void __exit smc_exit(void)
1990 {
1991         smc_core_exit();
1992         static_branch_disable(&tcp_have_smc);
1993         smc_ib_unregister_client();
1994         sock_unregister(PF_SMC);
1995         proto_unregister(&smc_proto6);
1996         proto_unregister(&smc_proto);
1997         smc_pnet_exit();
1998 }
1999
2000 module_init(smc_init);
2001 module_exit(smc_exit);
2002
2003 MODULE_AUTHOR("Ursula Braun <ubraun@linux.vnet.ibm.com>");
2004 MODULE_DESCRIPTION("smc socket address family");
2005 MODULE_LICENSE("GPL");
2006 MODULE_ALIAS_NETPROTO(PF_SMC);