net/smc/af_smc.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  Shared Memory Communications over RDMA (SMC-R) and RoCE
   4  *
   5  *  AF_SMC protocol family socket handler keeping the AF_INET sock address type
   6  *  applies to SOCK_STREAM sockets only
   7  *  offers an alternative communication option for TCP-protocol sockets
   8  *  applicable with RoCE-cards only
   9  *
  10  *  Initial restrictions:
  11  *    - support for alternate links postponed
  12  *
  13  *  Copyright IBM Corp. 2016, 2018
  14  *
  15  *  Author(s):  Ursula Braun <ubraun@linux.vnet.ibm.com>
  16  *              based on prototype from Frank Blaschka
  17  */
  18
  19 #define KMSG_COMPONENT "smc"
  20 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  21
  22 #include <linux/module.h>
  23 #include <linux/socket.h>
  24 #include <linux/workqueue.h>
  25 #include <linux/in.h>
  26 #include <linux/sched/signal.h>
  27 #include <linux/if_vlan.h>
  28 #include <linux/rcupdate_wait.h>
  29
  30 #include <net/sock.h>
  31 #include <net/tcp.h>
  32 #include <net/smc.h>
  33 #include <asm/ioctls.h>
  34
  35 #include <net/net_namespace.h>
  36 #include <net/netns/generic.h>
  37 #include "smc_netns.h"
  38
  39 #include "smc.h"
  40 #include "smc_clc.h"
  41 #include "smc_llc.h"
  42 #include "smc_cdc.h"
  43 #include "smc_core.h"
  44 #include "smc_ib.h"
  45 #include "smc_ism.h"
  46 #include "smc_pnet.h"
  47 #include "smc_tx.h"
  48 #include "smc_rx.h"
  49 #include "smc_close.h"
  50
  51 static DEFINE_MUTEX(smc_server_lgr_pending);    /* serialize link group
  52                                                  * creation on server
  53                                                  */
  54 static DEFINE_MUTEX(smc_client_lgr_pending);    /* serialize link group
  55                                                  * creation on client
  56                                                  */
  57
  58 static void smc_tcp_listen_work(struct work_struct *);
  59 static void smc_connect_work(struct work_struct *);
  60
  61 static void smc_set_keepalive(struct sock *sk, int val)
  62 {
  63         struct smc_sock *smc = smc_sk(sk);
  64
  65         smc->clcsock->sk->sk_prot->keepalive(smc->clcsock->sk, val);
  66 }
  67
  68 static struct smc_hashinfo smc_v4_hashinfo = {
  69         .lock = __RW_LOCK_UNLOCKED(smc_v4_hashinfo.lock),
  70 };
  71
  72 static struct smc_hashinfo smc_v6_hashinfo = {
  73         .lock = __RW_LOCK_UNLOCKED(smc_v6_hashinfo.lock),
  74 };
  75
  76 int smc_hash_sk(struct sock *sk)
  77 {
  78         struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
  79         struct hlist_head *head;
  80
  81         head = &h->ht;
  82
  83         write_lock_bh(&h->lock);
  84         sk_add_node(sk, head);
  85         sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
  86         write_unlock_bh(&h->lock);
  87
  88         return 0;
  89 }
  90 EXPORT_SYMBOL_GPL(smc_hash_sk);
  91
  92 void smc_unhash_sk(struct sock *sk)
  93 {
  94         struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
  95
  96         write_lock_bh(&h->lock);
  97         if (sk_del_node_init(sk))
  98                 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
  99         write_unlock_bh(&h->lock);
 100 }
 101 EXPORT_SYMBOL_GPL(smc_unhash_sk);
 102
 103 struct proto smc_proto = {
 104         .name           = "SMC",
 105         .owner          = THIS_MODULE,
 106         .keepalive      = smc_set_keepalive,
 107         .hash           = smc_hash_sk,
 108         .unhash         = smc_unhash_sk,
 109         .obj_size       = sizeof(struct smc_sock),
 110         .h.smc_hash     = &smc_v4_hashinfo,
 111         .slab_flags     = SLAB_TYPESAFE_BY_RCU,
 112 };
 113 EXPORT_SYMBOL_GPL(smc_proto);
 114
 115 struct proto smc_proto6 = {
 116         .name           = "SMC6",
 117         .owner          = THIS_MODULE,
 118         .keepalive      = smc_set_keepalive,
 119         .hash           = smc_hash_sk,
 120         .unhash         = smc_unhash_sk,
 121         .obj_size       = sizeof(struct smc_sock),
 122         .h.smc_hash     = &smc_v6_hashinfo,
 123         .slab_flags     = SLAB_TYPESAFE_BY_RCU,
 124 };
 125 EXPORT_SYMBOL_GPL(smc_proto6);
 126
 127 static void smc_restore_fallback_changes(struct smc_sock *smc)
 128 {
 129         smc->clcsock->file->private_data = smc->sk.sk_socket;
 130         smc->clcsock->file = NULL;
 131 }
 132
 133 static int __smc_release(struct smc_sock *smc)
 134 {
 135         struct sock *sk = &smc->sk;
 136         int rc = 0;
 137
 138         if (!smc->use_fallback) {
 139                 rc = smc_close_active(smc);
 140                 sock_set_flag(sk, SOCK_DEAD);
 141                 sk->sk_shutdown |= SHUTDOWN_MASK;
 142         } else {
 143                 if (sk->sk_state != SMC_LISTEN && sk->sk_state != SMC_INIT)
 144                         sock_put(sk); /* passive closing */
 145                 if (sk->sk_state == SMC_LISTEN) {
 146                         /* wake up clcsock accept */
 147                         rc = kernel_sock_shutdown(smc->clcsock, SHUT_RDWR);
 148                 }
 149                 sk->sk_state = SMC_CLOSED;
 150                 sk->sk_state_change(sk);
 151                 smc_restore_fallback_changes(smc);
 152         }
 153
 154         sk->sk_prot->unhash(sk);
 155
 156         if (sk->sk_state == SMC_CLOSED) {
 157                 if (smc->clcsock) {
 158                         release_sock(sk);
 159                         smc_clcsock_release(smc);
 160                         lock_sock(sk);
 161                 }
 162                 if (!smc->use_fallback)
 163                         smc_conn_free(&smc->conn);
 164         }
 165
 166         return rc;
 167 }
 168
 169 static int smc_release(struct socket *sock)
 170 {
 171         struct sock *sk = sock->sk;
 172         struct smc_sock *smc;
 173         int rc = 0;
 174
 175         if (!sk)
 176                 goto out;
 177
 178         sock_hold(sk); /* sock_put below */
 179         smc = smc_sk(sk);
 180
 181         /* cleanup for a dangling non-blocking connect */
 182         if (smc->connect_nonblock && sk->sk_state == SMC_INIT)
 183                 tcp_abort(smc->clcsock->sk, ECONNABORTED);
 184         flush_work(&smc->connect_work);
 185
 186         if (sk->sk_state == SMC_LISTEN)
 187                 /* smc_close_non_accepted() is called and acquires
 188                  * sock lock for child sockets again
 189                  */
 190                 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 191         else
 192                 lock_sock(sk);
 193
 194         rc = __smc_release(smc);
 195
 196         /* detach socket */
 197         sock_orphan(sk);
 198         sock->sk = NULL;
 199         release_sock(sk);
 200
 201         sock_put(sk); /* sock_hold above */
 202         sock_put(sk); /* final sock_put */
 203 out:
 204         return rc;
 205 }
 206
 207 static void smc_destruct(struct sock *sk)
 208 {
 209         if (sk->sk_state != SMC_CLOSED)
 210                 return;
 211         if (!sock_flag(sk, SOCK_DEAD))
 212                 return;
 213
 214         sk_refcnt_debug_dec(sk);
 215 }
 216
 217 static struct sock *smc_sock_alloc(struct net *net, struct socket *sock,
 218                                    int protocol)
 219 {
 220         struct smc_sock *smc;
 221         struct proto *prot;
 222         struct sock *sk;
 223
 224         prot = (protocol == SMCPROTO_SMC6) ? &smc_proto6 : &smc_proto;
 225         sk = sk_alloc(net, PF_SMC, GFP_KERNEL, prot, 0);
 226         if (!sk)
 227                 return NULL;
 228
 229         sock_init_data(sock, sk); /* sets sk_refcnt to 1 */
 230         sk->sk_state = SMC_INIT;
 231         sk->sk_destruct = smc_destruct;
 232         sk->sk_protocol = protocol;
 233         smc = smc_sk(sk);
 234         INIT_WORK(&smc->tcp_listen_work, smc_tcp_listen_work);
 235         INIT_WORK(&smc->connect_work, smc_connect_work);
 236         INIT_DELAYED_WORK(&smc->conn.tx_work, smc_tx_work);
 237         INIT_LIST_HEAD(&smc->accept_q);
 238         spin_lock_init(&smc->accept_q_lock);
 239         spin_lock_init(&smc->conn.send_lock);
 240         sk->sk_prot->hash(sk);
 241         sk_refcnt_debug_inc(sk);
 242         mutex_init(&smc->clcsock_release_lock);
 243
 244         return sk;
 245 }
 246
 247 static int smc_bind(struct socket *sock, struct sockaddr *uaddr,
 248                     int addr_len)
 249 {
 250         struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
 251         struct sock *sk = sock->sk;
 252         struct smc_sock *smc;
 253         int rc;
 254
 255         smc = smc_sk(sk);
 256
 257         /* replicate tests from inet_bind(), to be safe wrt. future changes */
 258         rc = -EINVAL;
 259         if (addr_len < sizeof(struct sockaddr_in))
 260                 goto out;
 261
 262         rc = -EAFNOSUPPORT;
 263         if (addr->sin_family != AF_INET &&
 264             addr->sin_family != AF_INET6 &&
 265             addr->sin_family != AF_UNSPEC)
 266                 goto out;
 267         /* accept AF_UNSPEC (mapped to AF_INET) only if s_addr is INADDR_ANY */
 268         if (addr->sin_family == AF_UNSPEC &&
 269             addr->sin_addr.s_addr != htonl(INADDR_ANY))
 270                 goto out;
 271
 272         lock_sock(sk);
 273
 274         /* Check if socket is already active */
 275         rc = -EINVAL;
 276         if (sk->sk_state != SMC_INIT || smc->connect_nonblock)
 277                 goto out_rel;
 278
 279         smc->clcsock->sk->sk_reuse = sk->sk_reuse;
 280         rc = kernel_bind(smc->clcsock, uaddr, addr_len);
 281
 282 out_rel:
 283         release_sock(sk);
 284 out:
 285         return rc;
 286 }
 287
 288 static void smc_copy_sock_settings(struct sock *nsk, struct sock *osk,
 289                                    unsigned long mask)
 290 {
 291         /* options we don't get control via setsockopt for */
 292         nsk->sk_type = osk->sk_type;
 293         nsk->sk_sndbuf = osk->sk_sndbuf;
 294         nsk->sk_rcvbuf = osk->sk_rcvbuf;
 295         nsk->sk_sndtimeo = osk->sk_sndtimeo;
 296         nsk->sk_rcvtimeo = osk->sk_rcvtimeo;
 297         nsk->sk_mark = osk->sk_mark;
 298         nsk->sk_priority = osk->sk_priority;
 299         nsk->sk_rcvlowat = osk->sk_rcvlowat;
 300         nsk->sk_bound_dev_if = osk->sk_bound_dev_if;
 301         nsk->sk_err = osk->sk_err;
 302
 303         nsk->sk_flags &= ~mask;
 304         nsk->sk_flags |= osk->sk_flags & mask;
 305 }
 306
 307 #define SK_FLAGS_SMC_TO_CLC ((1UL << SOCK_URGINLINE) | \
 308                              (1UL << SOCK_KEEPOPEN) | \
 309                              (1UL << SOCK_LINGER) | \
 310                              (1UL << SOCK_BROADCAST) | \
 311                              (1UL << SOCK_TIMESTAMP) | \
 312                              (1UL << SOCK_DBG) | \
 313                              (1UL << SOCK_RCVTSTAMP) | \
 314                              (1UL << SOCK_RCVTSTAMPNS) | \
 315                              (1UL << SOCK_LOCALROUTE) | \
 316                              (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
 317                              (1UL << SOCK_RXQ_OVFL) | \
 318                              (1UL << SOCK_WIFI_STATUS) | \
 319                              (1UL << SOCK_NOFCS) | \
 320                              (1UL << SOCK_FILTER_LOCKED) | \
 321                              (1UL << SOCK_TSTAMP_NEW))
 322 /* copy only relevant settings and flags of SOL_SOCKET level from smc to
 323  * clc socket (since smc is not called for these options from net/core)
 324  */
 325 static void smc_copy_sock_settings_to_clc(struct smc_sock *smc)
 326 {
 327         smc_copy_sock_settings(smc->clcsock->sk, &smc->sk, SK_FLAGS_SMC_TO_CLC);
 328 }
 329
 330 #define SK_FLAGS_CLC_TO_SMC ((1UL << SOCK_URGINLINE) | \
 331                              (1UL << SOCK_KEEPOPEN) | \
 332                              (1UL << SOCK_LINGER) | \
 333                              (1UL << SOCK_DBG))
 334 /* copy only settings and flags relevant for smc from clc to smc socket */
 335 static void smc_copy_sock_settings_to_smc(struct smc_sock *smc)
 336 {
 337         smc_copy_sock_settings(&smc->sk, smc->clcsock->sk, SK_FLAGS_CLC_TO_SMC);
 338 }
 339
 340 /* register a new rmb, send confirm_rkey msg to register with peer */
 341 static int smc_reg_rmb(struct smc_link *link, struct smc_buf_desc *rmb_desc,
 342                        bool conf_rkey)
 343 {
 344         if (!rmb_desc->wr_reg) {
 345                 /* register memory region for new rmb */
 346                 if (smc_wr_reg_send(link, rmb_desc->mr_rx[SMC_SINGLE_LINK])) {
 347                         rmb_desc->regerr = 1;
 348                         return -EFAULT;
 349                 }
 350                 rmb_desc->wr_reg = 1;
 351         }
 352         if (!conf_rkey)
 353                 return 0;
 354         /* exchange confirm_rkey msg with peer */
 355         if (smc_llc_do_confirm_rkey(link, rmb_desc)) {
 356                 rmb_desc->regerr = 1;
 357                 return -EFAULT;
 358         }
 359         return 0;
 360 }
 361
 362 static int smc_clnt_conf_first_link(struct smc_sock *smc)
 363 {
 364         struct net *net = sock_net(smc->clcsock->sk);
 365         struct smc_link_group *lgr = smc->conn.lgr;
 366         struct smc_link *link;
 367         int rest;
 368         int rc;
 369
 370         link = &lgr->lnk[SMC_SINGLE_LINK];
 371         /* receive CONFIRM LINK request from server over RoCE fabric */
 372         rest = wait_for_completion_interruptible_timeout(
 373                 &link->llc_confirm,
 374                 SMC_LLC_WAIT_FIRST_TIME);
 375         if (rest <= 0) {
 376                 struct smc_clc_msg_decline dclc;
 377
 378                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
 379                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
 380                 return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
 381         }
 382
 383         if (link->llc_confirm_rc)
 384                 return SMC_CLC_DECL_RMBE_EC;
 385
 386         rc = smc_ib_modify_qp_rts(link);
 387         if (rc)
 388                 return SMC_CLC_DECL_ERR_RDYLNK;
 389
 390         smc_wr_remember_qp_attr(link);
 391
 392         if (smc_reg_rmb(link, smc->conn.rmb_desc, false))
 393                 return SMC_CLC_DECL_ERR_REGRMB;
 394
 395         /* send CONFIRM LINK response over RoCE fabric */
 396         rc = smc_llc_send_confirm_link(link, SMC_LLC_RESP);
 397         if (rc < 0)
 398                 return SMC_CLC_DECL_TIMEOUT_CL;
 399
 400         /* receive ADD LINK request from server over RoCE fabric */
 401         rest = wait_for_completion_interruptible_timeout(&link->llc_add,
 402                                                          SMC_LLC_WAIT_TIME);
 403         if (rest <= 0) {
 404                 struct smc_clc_msg_decline dclc;
 405
 406                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
 407                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
 408                 return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_AL : rc;
 409         }
 410
 411         /* send add link reject message, only one link supported for now */
 412         rc = smc_llc_send_add_link(link,
 413                                    link->smcibdev->mac[link->ibport - 1],
 414                                    link->gid, SMC_LLC_RESP);
 415         if (rc < 0)
 416                 return SMC_CLC_DECL_TIMEOUT_AL;
 417
 418         smc_llc_link_active(link, net->ipv4.sysctl_tcp_keepalive_time);
 419
 420         return 0;
 421 }
 422
 423 static void smcr_conn_save_peer_info(struct smc_sock *smc,
 424                                      struct smc_clc_msg_accept_confirm *clc)
 425 {
 426         int bufsize = smc_uncompress_bufsize(clc->rmbe_size);
 427
 428         smc->conn.peer_rmbe_idx = clc->rmbe_idx;
 429         smc->conn.local_tx_ctrl.token = ntohl(clc->rmbe_alert_token);
 430         smc->conn.peer_rmbe_size = bufsize;
 431         atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
 432         smc->conn.tx_off = bufsize * (smc->conn.peer_rmbe_idx - 1);
 433 }
 434
 435 static void smcd_conn_save_peer_info(struct smc_sock *smc,
 436                                      struct smc_clc_msg_accept_confirm *clc)
 437 {
 438         int bufsize = smc_uncompress_bufsize(clc->dmbe_size);
 439
 440         smc->conn.peer_rmbe_idx = clc->dmbe_idx;
 441         smc->conn.peer_token = clc->token;
 442         /* msg header takes up space in the buffer */
 443         smc->conn.peer_rmbe_size = bufsize - sizeof(struct smcd_cdc_msg);
 444         atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
 445         smc->conn.tx_off = bufsize * smc->conn.peer_rmbe_idx;
 446 }
 447
 448 static void smc_conn_save_peer_info(struct smc_sock *smc,
 449                                     struct smc_clc_msg_accept_confirm *clc)
 450 {
 451         if (smc->conn.lgr->is_smcd)
 452                 smcd_conn_save_peer_info(smc, clc);
 453         else
 454                 smcr_conn_save_peer_info(smc, clc);
 455 }
 456
 457 static void smc_link_save_peer_info(struct smc_link *link,
 458                                     struct smc_clc_msg_accept_confirm *clc)
 459 {
 460         link->peer_qpn = ntoh24(clc->qpn);
 461         memcpy(link->peer_gid, clc->lcl.gid, SMC_GID_SIZE);
 462         memcpy(link->peer_mac, clc->lcl.mac, sizeof(link->peer_mac));
 463         link->peer_psn = ntoh24(clc->psn);
 464         link->peer_mtu = clc->qp_mtu;
 465 }
 466
 467 static void smc_switch_to_fallback(struct smc_sock *smc)
 468 {
 469         smc->use_fallback = true;
 470         if (smc->sk.sk_socket && smc->sk.sk_socket->file) {
 471                 smc->clcsock->file = smc->sk.sk_socket->file;
 472                 smc->clcsock->file->private_data = smc->clcsock;
 473         }
 474 }
 475
 476 /* fall back during connect */
 477 static int smc_connect_fallback(struct smc_sock *smc, int reason_code)
 478 {
 479         smc_switch_to_fallback(smc);
 480         smc->fallback_rsn = reason_code;
 481         smc_copy_sock_settings_to_clc(smc);
 482         smc->connect_nonblock = 0;
 483         if (smc->sk.sk_state == SMC_INIT)
 484                 smc->sk.sk_state = SMC_ACTIVE;
 485         return 0;
 486 }
 487
 488 /* decline and fall back during connect */
 489 static int smc_connect_decline_fallback(struct smc_sock *smc, int reason_code)
 490 {
 491         int rc;
 492
 493         if (reason_code < 0) { /* error, fallback is not possible */
 494                 if (smc->sk.sk_state == SMC_INIT)
 495                         sock_put(&smc->sk); /* passive closing */
 496                 return reason_code;
 497         }
 498         if (reason_code != SMC_CLC_DECL_PEERDECL) {
 499                 rc = smc_clc_send_decline(smc, reason_code);
 500                 if (rc < 0) {
 501                         if (smc->sk.sk_state == SMC_INIT)
 502                                 sock_put(&smc->sk); /* passive closing */
 503                         return rc;
 504                 }
 505         }
 506         return smc_connect_fallback(smc, reason_code);
 507 }
 508
 509 /* abort connecting */
 510 static int smc_connect_abort(struct smc_sock *smc, int reason_code,
 511                              int local_contact)
 512 {
 513         if (local_contact == SMC_FIRST_CONTACT)
 514                 smc_lgr_forget(smc->conn.lgr);
 515         if (smc->conn.lgr->is_smcd)
 516                 /* there is only one lgr role for SMC-D; use server lock */
 517                 mutex_unlock(&smc_server_lgr_pending);
 518         else
 519                 mutex_unlock(&smc_client_lgr_pending);
 520
 521         smc_conn_free(&smc->conn);
 522         smc->connect_nonblock = 0;
 523         return reason_code;
 524 }
 525
 526 /* check if there is a rdma device available for this connection. */
 527 /* called for connect and listen */
 528 static int smc_find_rdma_device(struct smc_sock *smc, struct smc_init_info *ini)
 529 {
 530         /* PNET table look up: search active ib_device and port
 531          * within same PNETID that also contains the ethernet device
 532          * used for the internal TCP socket
 533          */
 534         smc_pnet_find_roce_resource(smc->clcsock->sk, ini);
 535         if (!ini->ib_dev)
 536                 return SMC_CLC_DECL_NOSMCRDEV;
 537         return 0;
 538 }
 539
 540 /* check if there is an ISM device available for this connection. */
 541 /* called for connect and listen */
 542 static int smc_find_ism_device(struct smc_sock *smc, struct smc_init_info *ini)
 543 {
 544         /* Find ISM device with same PNETID as connecting interface  */
 545         smc_pnet_find_ism_resource(smc->clcsock->sk, ini);
 546         if (!ini->ism_dev)
 547                 return SMC_CLC_DECL_NOSMCDDEV;
 548         return 0;
 549 }
 550
 551 /* Check for VLAN ID and register it on ISM device just for CLC handshake */
 552 static int smc_connect_ism_vlan_setup(struct smc_sock *smc,
 553                                       struct smc_init_info *ini)
 554 {
 555         if (ini->vlan_id && smc_ism_get_vlan(ini->ism_dev, ini->vlan_id))
 556                 return SMC_CLC_DECL_ISMVLANERR;
 557         return 0;
 558 }
 559
 560 /* cleanup temporary VLAN ID registration used for CLC handshake. If ISM is
 561  * used, the VLAN ID will be registered again during the connection setup.
 562  */
 563 static int smc_connect_ism_vlan_cleanup(struct smc_sock *smc, bool is_smcd,
 564                                         struct smc_init_info *ini)
 565 {
 566         if (!is_smcd)
 567                 return 0;
 568         if (ini->vlan_id && smc_ism_put_vlan(ini->ism_dev, ini->vlan_id))
 569                 return SMC_CLC_DECL_CNFERR;
 570         return 0;
 571 }
 572
 573 /* CLC handshake during connect */
 574 static int smc_connect_clc(struct smc_sock *smc, int smc_type,
 575                            struct smc_clc_msg_accept_confirm *aclc,
 576                            struct smc_init_info *ini)
 577 {
 578         int rc = 0;
 579
 580         /* do inband token exchange */
 581         rc = smc_clc_send_proposal(smc, smc_type, ini);
 582         if (rc)
 583                 return rc;
 584         /* receive SMC Accept CLC message */
 585         return smc_clc_wait_msg(smc, aclc, sizeof(*aclc), SMC_CLC_ACCEPT,
 586                                 CLC_WAIT_TIME);
 587 }
 588
 589 /* setup for RDMA connection of client */
 590 static int smc_connect_rdma(struct smc_sock *smc,
 591                             struct smc_clc_msg_accept_confirm *aclc,
 592                             struct smc_init_info *ini)
 593 {
 594         struct smc_link *link;
 595         int reason_code = 0;
 596
 597         ini->is_smcd = false;
 598         ini->ib_lcl = &aclc->lcl;
 599         ini->ib_clcqpn = ntoh24(aclc->qpn);
 600         ini->srv_first_contact = aclc->hdr.flag;
 601
 602         mutex_lock(&smc_client_lgr_pending);
 603         reason_code = smc_conn_create(smc, ini);
 604         if (reason_code) {
 605                 mutex_unlock(&smc_client_lgr_pending);
 606                 return reason_code;
 607         }
 608         link = &smc->conn.lgr->lnk[SMC_SINGLE_LINK];
 609
 610         smc_conn_save_peer_info(smc, aclc);
 611
 612         /* create send buffer and rmb */
 613         if (smc_buf_create(smc, false))
 614                 return smc_connect_abort(smc, SMC_CLC_DECL_MEM,
 615                                          ini->cln_first_contact);
 616
 617         if (ini->cln_first_contact == SMC_FIRST_CONTACT)
 618                 smc_link_save_peer_info(link, aclc);
 619
 620         if (smc_rmb_rtoken_handling(&smc->conn, aclc))
 621                 return smc_connect_abort(smc, SMC_CLC_DECL_ERR_RTOK,
 622                                          ini->cln_first_contact);
 623
 624         smc_close_init(smc);
 625         smc_rx_init(smc);
 626
 627         if (ini->cln_first_contact == SMC_FIRST_CONTACT) {
 628                 if (smc_ib_ready_link(link))
 629                         return smc_connect_abort(smc, SMC_CLC_DECL_ERR_RDYLNK,
 630                                                  ini->cln_first_contact);
 631         } else {
 632                 if (smc_reg_rmb(link, smc->conn.rmb_desc, true))
 633                         return smc_connect_abort(smc, SMC_CLC_DECL_ERR_REGRMB,
 634                                                  ini->cln_first_contact);
 635         }
 636         smc_rmb_sync_sg_for_device(&smc->conn);
 637
 638         reason_code = smc_clc_send_confirm(smc);
 639         if (reason_code)
 640                 return smc_connect_abort(smc, reason_code,
 641                                          ini->cln_first_contact);
 642
 643         smc_tx_init(smc);
 644
 645         if (ini->cln_first_contact == SMC_FIRST_CONTACT) {
 646                 /* QP confirmation over RoCE fabric */
 647                 reason_code = smc_clnt_conf_first_link(smc);
 648                 if (reason_code)
 649                         return smc_connect_abort(smc, reason_code,
 650                                                  ini->cln_first_contact);
 651         }
 652         mutex_unlock(&smc_client_lgr_pending);
 653
 654         smc_copy_sock_settings_to_clc(smc);
 655         smc->connect_nonblock = 0;
 656         if (smc->sk.sk_state == SMC_INIT)
 657                 smc->sk.sk_state = SMC_ACTIVE;
 658
 659         return 0;
 660 }
 661
 662 /* setup for ISM connection of client */
 663 static int smc_connect_ism(struct smc_sock *smc,
 664                            struct smc_clc_msg_accept_confirm *aclc,
 665                            struct smc_init_info *ini)
 666 {
 667         int rc = 0;
 668
 669         ini->is_smcd = true;
 670         ini->ism_gid = aclc->gid;
 671         ini->srv_first_contact = aclc->hdr.flag;
 672
 673         /* there is only one lgr role for SMC-D; use server lock */
 674         mutex_lock(&smc_server_lgr_pending);
 675         rc = smc_conn_create(smc, ini);
 676         if (rc) {
 677                 mutex_unlock(&smc_server_lgr_pending);
 678                 return rc;
 679         }
 680
 681         /* Create send and receive buffers */
 682         if (smc_buf_create(smc, true))
 683                 return smc_connect_abort(smc, SMC_CLC_DECL_MEM,
 684                                          ini->cln_first_contact);
 685
 686         smc_conn_save_peer_info(smc, aclc);
 687         smc_close_init(smc);
 688         smc_rx_init(smc);
 689         smc_tx_init(smc);
 690
 691         rc = smc_clc_send_confirm(smc);
 692         if (rc)
 693                 return smc_connect_abort(smc, rc, ini->cln_first_contact);
 694         mutex_unlock(&smc_server_lgr_pending);
 695
 696         smc_copy_sock_settings_to_clc(smc);
 697         smc->connect_nonblock = 0;
 698         if (smc->sk.sk_state == SMC_INIT)
 699                 smc->sk.sk_state = SMC_ACTIVE;
 700
 701         return 0;
 702 }
 703
 704 /* perform steps before actually connecting */
 705 static int __smc_connect(struct smc_sock *smc)
 706 {
 707         bool ism_supported = false, rdma_supported = false;
 708         struct smc_clc_msg_accept_confirm aclc;
 709         struct smc_init_info ini = {0};
 710         int smc_type;
 711         int rc = 0;
 712
 713         if (smc->use_fallback)
 714                 return smc_connect_fallback(smc, smc->fallback_rsn);
 715
 716         /* if peer has not signalled SMC-capability, fall back */
 717         if (!tcp_sk(smc->clcsock->sk)->syn_smc)
 718                 return smc_connect_fallback(smc, SMC_CLC_DECL_PEERNOSMC);
 719
 720         /* IPSec connections opt out of SMC-R optimizations */
 721         if (using_ipsec(smc))
 722                 return smc_connect_decline_fallback(smc, SMC_CLC_DECL_IPSEC);
 723
 724         /* get vlan id from IP device */
 725         if (smc_vlan_by_tcpsk(smc->clcsock, &ini))
 726                 return smc_connect_decline_fallback(smc,
 727                                                     SMC_CLC_DECL_GETVLANERR);
 728
 729         /* check if there is an ism device available */
 730         if (!smc_find_ism_device(smc, &ini) &&
 731             !smc_connect_ism_vlan_setup(smc, &ini)) {
 732                 /* ISM is supported for this connection */
 733                 ism_supported = true;
 734                 smc_type = SMC_TYPE_D;
 735         }
 736
 737         /* check if there is a rdma device available */
 738         if (!smc_find_rdma_device(smc, &ini)) {
 739                 /* RDMA is supported for this connection */
 740                 rdma_supported = true;
 741                 if (ism_supported)
 742                         smc_type = SMC_TYPE_B; /* both */
 743                 else
 744                         smc_type = SMC_TYPE_R; /* only RDMA */
 745         }
 746
 747         /* if neither ISM nor RDMA are supported, fallback */
 748         if (!rdma_supported && !ism_supported)
 749                 return smc_connect_decline_fallback(smc, SMC_CLC_DECL_NOSMCDEV);
 750
 751         /* perform CLC handshake */
 752         rc = smc_connect_clc(smc, smc_type, &aclc, &ini);
 753         if (rc) {
 754                 smc_connect_ism_vlan_cleanup(smc, ism_supported, &ini);
 755                 return smc_connect_decline_fallback(smc, rc);
 756         }
 757
 758         /* depending on previous steps, connect using rdma or ism */
 759         if (rdma_supported && aclc.hdr.path == SMC_TYPE_R)
 760                 rc = smc_connect_rdma(smc, &aclc, &ini);
 761         else if (ism_supported && aclc.hdr.path == SMC_TYPE_D)
 762                 rc = smc_connect_ism(smc, &aclc, &ini);
 763         else
 764                 rc = SMC_CLC_DECL_MODEUNSUPP;
 765         if (rc) {
 766                 smc_connect_ism_vlan_cleanup(smc, ism_supported, &ini);
 767                 return smc_connect_decline_fallback(smc, rc);
 768         }
 769
 770         smc_connect_ism_vlan_cleanup(smc, ism_supported, &ini);
 771         return 0;
 772 }
 773
 774 static void smc_connect_work(struct work_struct *work)
 775 {
 776         struct smc_sock *smc = container_of(work, struct smc_sock,
 777                                             connect_work);
 778         long timeo = smc->sk.sk_sndtimeo;
 779         int rc = 0;
 780
 781         if (!timeo)
 782                 timeo = MAX_SCHEDULE_TIMEOUT;
 783         lock_sock(smc->clcsock->sk);
 784         if (smc->clcsock->sk->sk_err) {
 785                 smc->sk.sk_err = smc->clcsock->sk->sk_err;
 786         } else if ((1 << smc->clcsock->sk->sk_state) &
 787                                         (TCPF_SYN_SENT | TCP_SYN_RECV)) {
 788                 rc = sk_stream_wait_connect(smc->clcsock->sk, &timeo);
 789                 if ((rc == -EPIPE) &&
 790                     ((1 << smc->clcsock->sk->sk_state) &
 791                                         (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)))
 792                         rc = 0;
 793         }
 794         release_sock(smc->clcsock->sk);
 795         lock_sock(&smc->sk);
 796         if (rc != 0 || smc->sk.sk_err) {
 797                 smc->sk.sk_state = SMC_CLOSED;
 798                 if (rc == -EPIPE || rc == -EAGAIN)
 799                         smc->sk.sk_err = EPIPE;
 800                 else if (signal_pending(current))
 801                         smc->sk.sk_err = -sock_intr_errno(timeo);
 802                 sock_put(&smc->sk); /* passive closing */
 803                 goto out;
 804         }
 805
 806         rc = __smc_connect(smc);
 807         if (rc < 0)
 808                 smc->sk.sk_err = -rc;
 809
 810 out:
 811         if (!sock_flag(&smc->sk, SOCK_DEAD)) {
 812                 if (smc->sk.sk_err) {
 813                         smc->sk.sk_state_change(&smc->sk);
 814                 } else { /* allow polling before and after fallback decision */
 815                         smc->clcsock->sk->sk_write_space(smc->clcsock->sk);
 816                         smc->sk.sk_write_space(&smc->sk);
 817                 }
 818         }
 819         release_sock(&smc->sk);
 820 }
 821
 822 static int smc_connect(struct socket *sock, struct sockaddr *addr,
 823                        int alen, int flags)
 824 {
 825         struct sock *sk = sock->sk;
 826         struct smc_sock *smc;
 827         int rc = -EINVAL;
 828
 829         smc = smc_sk(sk);
 830
 831         /* separate smc parameter checking to be safe */
 832         if (alen < sizeof(addr->sa_family))
 833                 goto out_err;
 834         if (addr->sa_family != AF_INET && addr->sa_family != AF_INET6)
 835                 goto out_err;
 836
 837         lock_sock(sk);
 838         switch (sk->sk_state) {
 839         default:
 840                 goto out;
 841         case SMC_ACTIVE:
 842                 rc = -EISCONN;
 843                 goto out;
 844         case SMC_INIT:
 845                 rc = 0;
 846                 break;
 847         }
 848
 849         smc_copy_sock_settings_to_clc(smc);
 850         tcp_sk(smc->clcsock->sk)->syn_smc = 1;
 851         if (smc->connect_nonblock) {
 852                 rc = -EALREADY;
 853                 goto out;
 854         }
 855         rc = kernel_connect(smc->clcsock, addr, alen, flags);
 856         if (rc && rc != -EINPROGRESS)
 857                 goto out;
 858
 859         sock_hold(&smc->sk); /* sock put in passive closing */
 860         if (flags & O_NONBLOCK) {
 861                 if (schedule_work(&smc->connect_work))
 862                         smc->connect_nonblock = 1;
 863                 rc = -EINPROGRESS;
 864         } else {
 865                 rc = __smc_connect(smc);
 866                 if (rc < 0)
 867                         goto out;
 868                 else
 869                         rc = 0; /* success cases including fallback */
 870         }
 871
 872 out:
 873         release_sock(sk);
 874 out_err:
 875         return rc;
 876 }
 877
 878 static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc)
 879 {
 880         struct socket *new_clcsock = NULL;
 881         struct sock *lsk = &lsmc->sk;
 882         struct sock *new_sk;
 883         int rc = -EINVAL;
 884
 885         release_sock(lsk);
 886         new_sk = smc_sock_alloc(sock_net(lsk), NULL, lsk->sk_protocol);
 887         if (!new_sk) {
 888                 rc = -ENOMEM;
 889                 lsk->sk_err = ENOMEM;
 890                 *new_smc = NULL;
 891                 lock_sock(lsk);
 892                 goto out;
 893         }
 894         *new_smc = smc_sk(new_sk);
 895
 896         mutex_lock(&lsmc->clcsock_release_lock);
 897         if (lsmc->clcsock)
 898                 rc = kernel_accept(lsmc->clcsock, &new_clcsock, 0);
 899         mutex_unlock(&lsmc->clcsock_release_lock);
 900         lock_sock(lsk);
 901         if  (rc < 0)
 902                 lsk->sk_err = -rc;
 903         if (rc < 0 || lsk->sk_state == SMC_CLOSED) {
 904                 new_sk->sk_prot->unhash(new_sk);
 905                 if (new_clcsock)
 906                         sock_release(new_clcsock);
 907                 new_sk->sk_state = SMC_CLOSED;
 908                 sock_set_flag(new_sk, SOCK_DEAD);
 909                 sock_put(new_sk); /* final */
 910                 *new_smc = NULL;
 911                 goto out;
 912         }
 913
 914         (*new_smc)->clcsock = new_clcsock;
 915 out:
 916         return rc;
 917 }
 918
 919 /* add a just created sock to the accept queue of the listen sock as
 920  * candidate for a following socket accept call from user space
 921  */
 922 static void smc_accept_enqueue(struct sock *parent, struct sock *sk)
 923 {
 924         struct smc_sock *par = smc_sk(parent);
 925
 926         sock_hold(sk); /* sock_put in smc_accept_unlink () */
 927         spin_lock(&par->accept_q_lock);
 928         list_add_tail(&smc_sk(sk)->accept_q, &par->accept_q);
 929         spin_unlock(&par->accept_q_lock);
 930         sk_acceptq_added(parent);
 931 }
 932
 933 /* remove a socket from the accept queue of its parental listening socket */
 934 static void smc_accept_unlink(struct sock *sk)
 935 {
 936         struct smc_sock *par = smc_sk(sk)->listen_smc;
 937
 938         spin_lock(&par->accept_q_lock);
 939         list_del_init(&smc_sk(sk)->accept_q);
 940         spin_unlock(&par->accept_q_lock);
 941         sk_acceptq_removed(&smc_sk(sk)->listen_smc->sk);
 942         sock_put(sk); /* sock_hold in smc_accept_enqueue */
 943 }
 944
 945 /* remove a sock from the accept queue to bind it to a new socket created
 946  * for a socket accept call from user space
 947  */
 948 struct sock *smc_accept_dequeue(struct sock *parent,
 949                                 struct socket *new_sock)
 950 {
 951         struct smc_sock *isk, *n;
 952         struct sock *new_sk;
 953
 954         list_for_each_entry_safe(isk, n, &smc_sk(parent)->accept_q, accept_q) {
 955                 new_sk = (struct sock *)isk;
 956
 957                 smc_accept_unlink(new_sk);
 958                 if (new_sk->sk_state == SMC_CLOSED) {
 959                         new_sk->sk_prot->unhash(new_sk);
 960                         if (isk->clcsock) {
 961                                 sock_release(isk->clcsock);
 962                                 isk->clcsock = NULL;
 963                         }
 964                         sock_put(new_sk); /* final */
 965                         continue;
 966                 }
 967                 if (new_sock) {
 968                         sock_graft(new_sk, new_sock);
 969                         if (isk->use_fallback) {
 970                                 smc_sk(new_sk)->clcsock->file = new_sock->file;
 971                                 isk->clcsock->file->private_data = isk->clcsock;
 972                         }
 973                 }
 974                 return new_sk;
 975         }
 976         return NULL;
 977 }
 978
 979 /* clean up for a created but never accepted sock */
 980 void smc_close_non_accepted(struct sock *sk)
 981 {
 982         struct smc_sock *smc = smc_sk(sk);
 983
 984         sock_hold(sk); /* sock_put below */
 985         lock_sock(sk);
 986         if (!sk->sk_lingertime)
 987                 /* wait for peer closing */
 988                 sk->sk_lingertime = SMC_MAX_STREAM_WAIT_TIMEOUT;
 989         __smc_release(smc);
 990         release_sock(sk);
 991         sock_put(sk); /* sock_hold above */
 992         sock_put(sk); /* final sock_put */
 993 }
 994
 995 static int smc_serv_conf_first_link(struct smc_sock *smc)
 996 {
 997         struct net *net = sock_net(smc->clcsock->sk);
 998         struct smc_link_group *lgr = smc->conn.lgr;
 999         struct smc_link *link;
1000         int rest;
1001         int rc;
1002
1003         link = &lgr->lnk[SMC_SINGLE_LINK];
1004
1005         if (smc_reg_rmb(link, smc->conn.rmb_desc, false))
1006                 return SMC_CLC_DECL_ERR_REGRMB;
1007
1008         /* send CONFIRM LINK request to client over the RoCE fabric */
1009         rc = smc_llc_send_confirm_link(link, SMC_LLC_REQ);
1010         if (rc < 0)
1011                 return SMC_CLC_DECL_TIMEOUT_CL;
1012
1013         /* receive CONFIRM LINK response from client over the RoCE fabric */
1014         rest = wait_for_completion_interruptible_timeout(
1015                 &link->llc_confirm_resp,
1016                 SMC_LLC_WAIT_FIRST_TIME);
1017         if (rest <= 0) {
1018                 struct smc_clc_msg_decline dclc;
1019
1020                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
1021                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
1022                 return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
1023         }
1024
1025         if (link->llc_confirm_resp_rc)
1026                 return SMC_CLC_DECL_RMBE_EC;
1027
1028         /* send ADD LINK request to client over the RoCE fabric */
1029         rc = smc_llc_send_add_link(link,
1030                                    link->smcibdev->mac[link->ibport - 1],
1031                                    link->gid, SMC_LLC_REQ);
1032         if (rc < 0)
1033                 return SMC_CLC_DECL_TIMEOUT_AL;
1034
1035         /* receive ADD LINK response from client over the RoCE fabric */
1036         rest = wait_for_completion_interruptible_timeout(&link->llc_add_resp,
1037                                                          SMC_LLC_WAIT_TIME);
1038         if (rest <= 0) {
1039                 struct smc_clc_msg_decline dclc;
1040
1041                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
1042                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
1043                 return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_AL : rc;
1044         }
1045
1046         smc_llc_link_active(link, net->ipv4.sysctl_tcp_keepalive_time);
1047
1048         return 0;
1049 }
1050
1051 /* listen worker: finish */
1052 static void smc_listen_out(struct smc_sock *new_smc)
1053 {
1054         struct smc_sock *lsmc = new_smc->listen_smc;
1055         struct sock *newsmcsk = &new_smc->sk;
1056
1057         if (lsmc->sk.sk_state == SMC_LISTEN) {
1058                 lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING);
1059                 smc_accept_enqueue(&lsmc->sk, newsmcsk);
1060                 release_sock(&lsmc->sk);
1061         } else { /* no longer listening */
1062                 smc_close_non_accepted(newsmcsk);
1063         }
1064
1065         /* Wake up accept */
1066         lsmc->sk.sk_data_ready(&lsmc->sk);
1067         sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */
1068 }
1069
1070 /* listen worker: finish in state connected */
1071 static void smc_listen_out_connected(struct smc_sock *new_smc)
1072 {
1073         struct sock *newsmcsk = &new_smc->sk;
1074
1075         sk_refcnt_debug_inc(newsmcsk);
1076         if (newsmcsk->sk_state == SMC_INIT)
1077                 newsmcsk->sk_state = SMC_ACTIVE;
1078
1079         smc_listen_out(new_smc);
1080 }
1081
1082 /* listen worker: finish in error state */
1083 static void smc_listen_out_err(struct smc_sock *new_smc)
1084 {
1085         struct sock *newsmcsk = &new_smc->sk;
1086
1087         if (newsmcsk->sk_state == SMC_INIT)
1088                 sock_put(&new_smc->sk); /* passive closing */
1089         newsmcsk->sk_state = SMC_CLOSED;
1090         smc_conn_free(&new_smc->conn);
1091
1092         smc_listen_out(new_smc);
1093 }
1094
1095 /* listen worker: decline and fall back if possible */
1096 static void smc_listen_decline(struct smc_sock *new_smc, int reason_code,
1097                                int local_contact)
1098 {
1099         /* RDMA setup failed, switch back to TCP */
1100         if (local_contact == SMC_FIRST_CONTACT)
1101                 smc_lgr_forget(new_smc->conn.lgr);
1102         if (reason_code < 0) { /* error, no fallback possible */
1103                 smc_listen_out_err(new_smc);
1104                 return;
1105         }
1106         smc_conn_free(&new_smc->conn);
1107         smc_switch_to_fallback(new_smc);
1108         new_smc->fallback_rsn = reason_code;
1109         if (reason_code && reason_code != SMC_CLC_DECL_PEERDECL) {
1110                 if (smc_clc_send_decline(new_smc, reason_code) < 0) {
1111                         smc_listen_out_err(new_smc);
1112                         return;
1113                 }
1114         }
1115         smc_listen_out_connected(new_smc);
1116 }
1117
1118 /* listen worker: check prefixes */
1119 static int smc_listen_prfx_check(struct smc_sock *new_smc,
1120                                  struct smc_clc_msg_proposal *pclc)
1121 {
1122         struct smc_clc_msg_proposal_prefix *pclc_prfx;
1123         struct socket *newclcsock = new_smc->clcsock;
1124
1125         pclc_prfx = smc_clc_proposal_get_prefix(pclc);
1126         if (smc_clc_prfx_match(newclcsock, pclc_prfx))
1127                 return SMC_CLC_DECL_DIFFPREFIX;
1128
1129         return 0;
1130 }
1131
1132 /* listen worker: initialize connection and buffers */
1133 static int smc_listen_rdma_init(struct smc_sock *new_smc,
1134                                 struct smc_init_info *ini)
1135 {
1136         int rc;
1137
1138         /* allocate connection / link group */
1139         rc = smc_conn_create(new_smc, ini);
1140         if (rc)
1141                 return rc;
1142
1143         /* create send buffer and rmb */
1144         if (smc_buf_create(new_smc, false))
1145                 return SMC_CLC_DECL_MEM;
1146
1147         return 0;
1148 }
1149
1150 /* listen worker: initialize connection and buffers for SMC-D */
1151 static int smc_listen_ism_init(struct smc_sock *new_smc,
1152                                struct smc_clc_msg_proposal *pclc,
1153                                struct smc_init_info *ini)
1154 {
1155         struct smc_clc_msg_smcd *pclc_smcd;
1156         int rc;
1157
1158         pclc_smcd = smc_get_clc_msg_smcd(pclc);
1159         ini->ism_gid = pclc_smcd->gid;
1160         rc = smc_conn_create(new_smc, ini);
1161         if (rc)
1162                 return rc;
1163
1164         /* Check if peer can be reached via ISM device */
1165         if (smc_ism_cantalk(new_smc->conn.lgr->peer_gid,
1166                             new_smc->conn.lgr->vlan_id,
1167                             new_smc->conn.lgr->smcd)) {
1168                 if (ini->cln_first_contact == SMC_FIRST_CONTACT)
1169                         smc_lgr_forget(new_smc->conn.lgr);
1170                 smc_conn_free(&new_smc->conn);
1171                 return SMC_CLC_DECL_SMCDNOTALK;
1172         }
1173
1174         /* Create send and receive buffers */
1175         if (smc_buf_create(new_smc, true)) {
1176                 if (ini->cln_first_contact == SMC_FIRST_CONTACT)
1177                         smc_lgr_forget(new_smc->conn.lgr);
1178                 smc_conn_free(&new_smc->conn);
1179                 return SMC_CLC_DECL_MEM;
1180         }
1181
1182         return 0;
1183 }
1184
1185 /* listen worker: register buffers */
1186 static int smc_listen_rdma_reg(struct smc_sock *new_smc, int local_contact)
1187 {
1188         struct smc_link *link = &new_smc->conn.lgr->lnk[SMC_SINGLE_LINK];
1189
1190         if (local_contact != SMC_FIRST_CONTACT) {
1191                 if (smc_reg_rmb(link, new_smc->conn.rmb_desc, true))
1192                         return SMC_CLC_DECL_ERR_REGRMB;
1193         }
1194         smc_rmb_sync_sg_for_device(&new_smc->conn);
1195
1196         return 0;
1197 }
1198
1199 /* listen worker: finish RDMA setup */
1200 static int smc_listen_rdma_finish(struct smc_sock *new_smc,
1201                                   struct smc_clc_msg_accept_confirm *cclc,
1202                                   int local_contact)
1203 {
1204         struct smc_link *link = &new_smc->conn.lgr->lnk[SMC_SINGLE_LINK];
1205         int reason_code = 0;
1206
1207         if (local_contact == SMC_FIRST_CONTACT)
1208                 smc_link_save_peer_info(link, cclc);
1209
1210         if (smc_rmb_rtoken_handling(&new_smc->conn, cclc)) {
1211                 reason_code = SMC_CLC_DECL_ERR_RTOK;
1212                 goto decline;
1213         }
1214
1215         if (local_contact == SMC_FIRST_CONTACT) {
1216                 if (smc_ib_ready_link(link)) {
1217                         reason_code = SMC_CLC_DECL_ERR_RDYLNK;
1218                         goto decline;
1219                 }
1220                 /* QP confirmation over RoCE fabric */
1221                 reason_code = smc_serv_conf_first_link(new_smc);
1222                 if (reason_code)
1223                         goto decline;
1224         }
1225         return 0;
1226
1227 decline:
1228         smc_listen_decline(new_smc, reason_code, local_contact);
1229         return reason_code;
1230 }
1231
1232 /* setup for RDMA connection of server */
1233 static void smc_listen_work(struct work_struct *work)
1234 {
1235         struct smc_sock *new_smc = container_of(work, struct smc_sock,
1236                                                 smc_listen_work);
1237         struct socket *newclcsock = new_smc->clcsock;
1238         struct smc_clc_msg_accept_confirm cclc;
1239         struct smc_clc_msg_proposal *pclc;
1240         struct smc_init_info ini = {0};
1241         bool ism_supported = false;
1242         u8 buf[SMC_CLC_MAX_LEN];
1243         int rc = 0;
1244
1245         if (new_smc->listen_smc->sk.sk_state != SMC_LISTEN)
1246                 return smc_listen_out_err(new_smc);
1247
1248         if (new_smc->use_fallback) {
1249                 smc_listen_out_connected(new_smc);
1250                 return;
1251         }
1252
1253         /* check if peer is smc capable */
1254         if (!tcp_sk(newclcsock->sk)->syn_smc) {
1255                 smc_switch_to_fallback(new_smc);
1256                 new_smc->fallback_rsn = SMC_CLC_DECL_PEERNOSMC;
1257                 smc_listen_out_connected(new_smc);
1258                 return;
1259         }
1260
1261         /* do inband token exchange -
1262          * wait for and receive SMC Proposal CLC message
1263          */
1264         pclc = (struct smc_clc_msg_proposal *)&buf;
1265         rc = smc_clc_wait_msg(new_smc, pclc, SMC_CLC_MAX_LEN,
1266                               SMC_CLC_PROPOSAL, CLC_WAIT_TIME);
1267         if (rc)
1268                 goto out_decl;
1269
1270         /* IPSec connections opt out of SMC-R optimizations */
1271         if (using_ipsec(new_smc)) {
1272                 rc = SMC_CLC_DECL_IPSEC;
1273                 goto out_decl;
1274         }
1275
1276         /* check for matching IP prefix and subnet length */
1277         rc = smc_listen_prfx_check(new_smc, pclc);
1278         if (rc)
1279                 goto out_decl;
1280
1281         /* get vlan id from IP device */
1282         if (smc_vlan_by_tcpsk(new_smc->clcsock, &ini)) {
1283                 rc = SMC_CLC_DECL_GETVLANERR;
1284                 goto out_decl;
1285         }
1286
1287         mutex_lock(&smc_server_lgr_pending);
1288         smc_close_init(new_smc);
1289         smc_rx_init(new_smc);
1290         smc_tx_init(new_smc);
1291
1292         /* check if ISM is available */
1293         if (pclc->hdr.path == SMC_TYPE_D || pclc->hdr.path == SMC_TYPE_B) {
1294                 ini.is_smcd = true; /* prepare ISM check */
1295                 rc = smc_find_ism_device(new_smc, &ini);
1296                 if (!rc)
1297                         rc = smc_listen_ism_init(new_smc, pclc, &ini);
1298                 if (!rc)
1299                         ism_supported = true;
1300                 else if (pclc->hdr.path == SMC_TYPE_D)
1301                         goto out_unlock; /* skip RDMA and decline */
1302         }
1303
1304         /* check if RDMA is available */
1305         if (!ism_supported) { /* SMC_TYPE_R or SMC_TYPE_B */
1306                 /* prepare RDMA check */
1307                 ini.is_smcd = false;
1308                 ini.ism_dev = NULL;
1309                 ini.ib_lcl = &pclc->lcl;
1310                 rc = smc_find_rdma_device(new_smc, &ini);
1311                 if (rc) {
1312                         /* no RDMA device found */
1313                         if (pclc->hdr.path == SMC_TYPE_B)
1314                                 /* neither ISM nor RDMA device found */
1315                                 rc = SMC_CLC_DECL_NOSMCDEV;
1316                         goto out_unlock;
1317                 }
1318                 rc = smc_listen_rdma_init(new_smc, &ini);
1319                 if (rc)
1320                         goto out_unlock;
1321                 rc = smc_listen_rdma_reg(new_smc, ini.cln_first_contact);
1322                 if (rc)
1323                         goto out_unlock;
1324         }
1325
1326         /* send SMC Accept CLC message */
1327         rc = smc_clc_send_accept(new_smc, ini.cln_first_contact);
1328         if (rc)
1329                 goto out_unlock;
1330
1331         /* SMC-D does not need this lock any more */
1332         if (ism_supported)
1333                 mutex_unlock(&smc_server_lgr_pending);
1334
1335         /* receive SMC Confirm CLC message */
1336         rc = smc_clc_wait_msg(new_smc, &cclc, sizeof(cclc),
1337                               SMC_CLC_CONFIRM, CLC_WAIT_TIME);
1338         if (rc) {
1339                 if (!ism_supported)
1340                         goto out_unlock;
1341                 goto out_decl;
1342         }
1343
1344         /* finish worker */
1345         if (!ism_supported) {
1346                 rc = smc_listen_rdma_finish(new_smc, &cclc,
1347                                             ini.cln_first_contact);
1348                 mutex_unlock(&smc_server_lgr_pending);
1349                 if (rc)
1350                         return;
1351         }
1352         smc_conn_save_peer_info(new_smc, &cclc);
1353         smc_listen_out_connected(new_smc);
1354         return;
1355
1356 out_unlock:
1357         mutex_unlock(&smc_server_lgr_pending);
1358 out_decl:
1359         smc_listen_decline(new_smc, rc, ini.cln_first_contact);
1360 }
1361
1362 static void smc_tcp_listen_work(struct work_struct *work)
1363 {
1364         struct smc_sock *lsmc = container_of(work, struct smc_sock,
1365                                              tcp_listen_work);
1366         struct sock *lsk = &lsmc->sk;
1367         struct smc_sock *new_smc;
1368         int rc = 0;
1369
1370         lock_sock(lsk);
1371         while (lsk->sk_state == SMC_LISTEN) {
1372                 rc = smc_clcsock_accept(lsmc, &new_smc);
1373                 if (rc)
1374                         goto out;
1375                 if (!new_smc)
1376                         continue;
1377
1378                 new_smc->listen_smc = lsmc;
1379                 new_smc->use_fallback = lsmc->use_fallback;
1380                 new_smc->fallback_rsn = lsmc->fallback_rsn;
1381                 sock_hold(lsk); /* sock_put in smc_listen_work */
1382                 INIT_WORK(&new_smc->smc_listen_work, smc_listen_work);
1383                 smc_copy_sock_settings_to_smc(new_smc);
1384                 new_smc->sk.sk_sndbuf = lsmc->sk.sk_sndbuf;
1385                 new_smc->sk.sk_rcvbuf = lsmc->sk.sk_rcvbuf;
1386                 sock_hold(&new_smc->sk); /* sock_put in passive closing */
1387                 if (!schedule_work(&new_smc->smc_listen_work))
1388                         sock_put(&new_smc->sk);
1389         }
1390
1391 out:
1392         release_sock(lsk);
1393         sock_put(&lsmc->sk); /* sock_hold in smc_listen */
1394 }
1395
1396 static int smc_listen(struct socket *sock, int backlog)
1397 {
1398         struct sock *sk = sock->sk;
1399         struct smc_sock *smc;
1400         int rc;
1401
1402         smc = smc_sk(sk);
1403         lock_sock(sk);
1404
1405         rc = -EINVAL;
1406         if ((sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) ||
1407             smc->connect_nonblock)
1408                 goto out;
1409
1410         rc = 0;
1411         if (sk->sk_state == SMC_LISTEN) {
1412                 sk->sk_max_ack_backlog = backlog;
1413                 goto out;
1414         }
1415         /* some socket options are handled in core, so we could not apply
1416          * them to the clc socket -- copy smc socket options to clc socket
1417          */
1418         smc_copy_sock_settings_to_clc(smc);
1419         if (!smc->use_fallback)
1420                 tcp_sk(smc->clcsock->sk)->syn_smc = 1;
1421
1422         rc = kernel_listen(smc->clcsock, backlog);
1423         if (rc)
1424                 goto out;
1425         sk->sk_max_ack_backlog = backlog;
1426         sk->sk_ack_backlog = 0;
1427         sk->sk_state = SMC_LISTEN;
1428         sock_hold(sk); /* sock_hold in tcp_listen_worker */
1429         if (!schedule_work(&smc->tcp_listen_work))
1430                 sock_put(sk);
1431
1432 out:
1433         release_sock(sk);
1434         return rc;
1435 }
1436
1437 static int smc_accept(struct socket *sock, struct socket *new_sock,
1438                       int flags, bool kern)
1439 {
1440         struct sock *sk = sock->sk, *nsk;
1441         DECLARE_WAITQUEUE(wait, current);
1442         struct smc_sock *lsmc;
1443         long timeo;
1444         int rc = 0;
1445
1446         lsmc = smc_sk(sk);
1447         sock_hold(sk); /* sock_put below */
1448         lock_sock(sk);
1449
1450         if (lsmc->sk.sk_state != SMC_LISTEN) {
1451                 rc = -EINVAL;
1452                 release_sock(sk);
1453                 goto out;
1454         }
1455
1456         /* Wait for an incoming connection */
1457         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
1458         add_wait_queue_exclusive(sk_sleep(sk), &wait);
1459         while (!(nsk = smc_accept_dequeue(sk, new_sock))) {
1460                 set_current_state(TASK_INTERRUPTIBLE);
1461                 if (!timeo) {
1462                         rc = -EAGAIN;
1463                         break;
1464                 }
1465                 release_sock(sk);
1466                 timeo = schedule_timeout(timeo);
1467                 /* wakeup by sk_data_ready in smc_listen_work() */
1468                 sched_annotate_sleep();
1469                 lock_sock(sk);
1470                 if (signal_pending(current)) {
1471                         rc = sock_intr_errno(timeo);
1472                         break;
1473                 }
1474         }
1475         set_current_state(TASK_RUNNING);
1476         remove_wait_queue(sk_sleep(sk), &wait);
1477
1478         if (!rc)
1479                 rc = sock_error(nsk);
1480         release_sock(sk);
1481         if (rc)
1482                 goto out;
1483
1484         if (lsmc->sockopt_defer_accept && !(flags & O_NONBLOCK)) {
1485                 /* wait till data arrives on the socket */
1486                 timeo = msecs_to_jiffies(lsmc->sockopt_defer_accept *
1487                                                                 MSEC_PER_SEC);
1488                 if (smc_sk(nsk)->use_fallback) {
1489                         struct sock *clcsk = smc_sk(nsk)->clcsock->sk;
1490
1491                         lock_sock(clcsk);
1492                         if (skb_queue_empty(&clcsk->sk_receive_queue))
1493                                 sk_wait_data(clcsk, &timeo, NULL);
1494                         release_sock(clcsk);
1495                 } else if (!atomic_read(&smc_sk(nsk)->conn.bytes_to_rcv)) {
1496                         lock_sock(nsk);
1497                         smc_rx_wait(smc_sk(nsk), &timeo, smc_rx_data_available);
1498                         release_sock(nsk);
1499                 }
1500         }
1501
1502 out:
1503         sock_put(sk); /* sock_hold above */
1504         return rc;
1505 }
1506
1507 static int smc_getname(struct socket *sock, struct sockaddr *addr,
1508                        int peer)
1509 {
1510         struct smc_sock *smc;
1511
1512         if (peer && (sock->sk->sk_state != SMC_ACTIVE) &&
1513             (sock->sk->sk_state != SMC_APPCLOSEWAIT1))
1514                 return -ENOTCONN;
1515
1516         smc = smc_sk(sock->sk);
1517
1518         return smc->clcsock->ops->getname(smc->clcsock, addr, peer);
1519 }
1520
1521 static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1522 {
1523         struct sock *sk = sock->sk;
1524         struct smc_sock *smc;
1525         int rc = -EPIPE;
1526
1527         smc = smc_sk(sk);
1528         lock_sock(sk);
1529         if ((sk->sk_state != SMC_ACTIVE) &&
1530             (sk->sk_state != SMC_APPCLOSEWAIT1) &&
1531             (sk->sk_state != SMC_INIT))
1532                 goto out;
1533
1534         if (msg->msg_flags & MSG_FASTOPEN) {
1535                 if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
1536                         smc_switch_to_fallback(smc);
1537                         smc->fallback_rsn = SMC_CLC_DECL_OPTUNSUPP;
1538                 } else {
1539                         rc = -EINVAL;
1540                         goto out;
1541                 }
1542         }
1543
1544         if (smc->use_fallback)
1545                 rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len);
1546         else
1547                 rc = smc_tx_sendmsg(smc, msg, len);
1548 out:
1549         release_sock(sk);
1550         return rc;
1551 }
1552
1553 static int smc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
1554                        int flags)
1555 {
1556         struct sock *sk = sock->sk;
1557         struct smc_sock *smc;
1558         int rc = -ENOTCONN;
1559
1560         smc = smc_sk(sk);
1561         lock_sock(sk);
1562         if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
1563                 /* socket was connected before, no more data to read */
1564                 rc = 0;
1565                 goto out;
1566         }
1567         if ((sk->sk_state == SMC_INIT) ||
1568             (sk->sk_state == SMC_LISTEN) ||
1569             (sk->sk_state == SMC_CLOSED))
1570                 goto out;
1571
1572         if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
1573                 rc = 0;
1574                 goto out;
1575         }
1576
1577         if (smc->use_fallback) {
1578                 rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags);
1579         } else {
1580                 msg->msg_namelen = 0;
1581                 rc = smc_rx_recvmsg(smc, msg, NULL, len, flags);
1582         }
1583
1584 out:
1585         release_sock(sk);
1586         return rc;
1587 }
1588
1589 static __poll_t smc_accept_poll(struct sock *parent)
1590 {
1591         struct smc_sock *isk = smc_sk(parent);
1592         __poll_t mask = 0;
1593
1594         spin_lock(&isk->accept_q_lock);
1595         if (!list_empty(&isk->accept_q))
1596                 mask = EPOLLIN | EPOLLRDNORM;
1597         spin_unlock(&isk->accept_q_lock);
1598
1599         return mask;
1600 }
1601
1602 static __poll_t smc_poll(struct file *file, struct socket *sock,
1603                              poll_table *wait)
1604 {
1605         struct sock *sk = sock->sk;
1606         struct smc_sock *smc;
1607         __poll_t mask = 0;
1608
1609         if (!sk)
1610                 return EPOLLNVAL;
1611
1612         smc = smc_sk(sock->sk);
1613         if (smc->use_fallback) {
1614                 /* delegate to CLC child sock */
1615                 mask = smc->clcsock->ops->poll(file, smc->clcsock, wait);
1616                 sk->sk_err = smc->clcsock->sk->sk_err;
1617         } else {
1618                 if (sk->sk_state != SMC_CLOSED)
1619                         sock_poll_wait(file, sock, wait);
1620                 if (sk->sk_err)
1621                         mask |= EPOLLERR;
1622                 if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
1623                     (sk->sk_state == SMC_CLOSED))
1624                         mask |= EPOLLHUP;
1625                 if (sk->sk_state == SMC_LISTEN) {
1626                         /* woken up by sk_data_ready in smc_listen_work() */
1627                         mask |= smc_accept_poll(sk);
1628                 } else if (smc->use_fallback) { /* as result of connect_work()*/
1629                         mask |= smc->clcsock->ops->poll(file, smc->clcsock,
1630                                                            wait);
1631                         sk->sk_err = smc->clcsock->sk->sk_err;
1632                 } else {
1633                         if ((sk->sk_state != SMC_INIT &&
1634                              atomic_read(&smc->conn.sndbuf_space)) ||
1635                             sk->sk_shutdown & SEND_SHUTDOWN) {
1636                                 mask |= EPOLLOUT | EPOLLWRNORM;
1637                         } else {
1638                                 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1639                                 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1640                         }
1641                         if (atomic_read(&smc->conn.bytes_to_rcv))
1642                                 mask |= EPOLLIN | EPOLLRDNORM;
1643                         if (sk->sk_shutdown & RCV_SHUTDOWN)
1644                                 mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
1645                         if (sk->sk_state == SMC_APPCLOSEWAIT1)
1646                                 mask |= EPOLLIN;
1647                         if (smc->conn.urg_state == SMC_URG_VALID)
1648                                 mask |= EPOLLPRI;
1649                 }
1650         }
1651
1652         return mask;
1653 }
1654
1655 static int smc_shutdown(struct socket *sock, int how)
1656 {
1657         struct sock *sk = sock->sk;
1658         struct smc_sock *smc;
1659         int rc = -EINVAL;
1660         int rc1 = 0;
1661
1662         smc = smc_sk(sk);
1663
1664         if ((how < SHUT_RD) || (how > SHUT_RDWR))
1665                 return rc;
1666
1667         lock_sock(sk);
1668
1669         rc = -ENOTCONN;
1670         if ((sk->sk_state != SMC_ACTIVE) &&
1671             (sk->sk_state != SMC_PEERCLOSEWAIT1) &&
1672             (sk->sk_state != SMC_PEERCLOSEWAIT2) &&
1673             (sk->sk_state != SMC_APPCLOSEWAIT1) &&
1674             (sk->sk_state != SMC_APPCLOSEWAIT2) &&
1675             (sk->sk_state != SMC_APPFINCLOSEWAIT))
1676                 goto out;
1677         if (smc->use_fallback) {
1678                 rc = kernel_sock_shutdown(smc->clcsock, how);
1679                 sk->sk_shutdown = smc->clcsock->sk->sk_shutdown;
1680                 if (sk->sk_shutdown == SHUTDOWN_MASK)
1681                         sk->sk_state = SMC_CLOSED;
1682                 goto out;
1683         }
1684         switch (how) {
1685         case SHUT_RDWR:         /* shutdown in both directions */
1686                 rc = smc_close_active(smc);
1687                 break;
1688         case SHUT_WR:
1689                 rc = smc_close_shutdown_write(smc);
1690                 break;
1691         case SHUT_RD:
1692                 rc = 0;
1693                 /* nothing more to do because peer is not involved */
1694                 break;
1695         }
1696         if (smc->clcsock)
1697                 rc1 = kernel_sock_shutdown(smc->clcsock, how);
1698         /* map sock_shutdown_cmd constants to sk_shutdown value range */
1699         sk->sk_shutdown |= how + 1;
1700
1701 out:
1702         release_sock(sk);
1703         return rc ? rc : rc1;
1704 }
1705
1706 static int smc_setsockopt(struct socket *sock, int level, int optname,
1707                           char __user *optval, unsigned int optlen)
1708 {
1709         struct sock *sk = sock->sk;
1710         struct smc_sock *smc;
1711         int val, rc;
1712
1713         smc = smc_sk(sk);
1714
1715         /* generic setsockopts reaching us here always apply to the
1716          * CLC socket
1717          */
1718         rc = smc->clcsock->ops->setsockopt(smc->clcsock, level, optname,
1719                                            optval, optlen);
1720         if (smc->clcsock->sk->sk_err) {
1721                 sk->sk_err = smc->clcsock->sk->sk_err;
1722                 sk->sk_error_report(sk);
1723         }
1724         if (rc)
1725                 return rc;
1726
1727         if (optlen < sizeof(int))
1728                 return -EINVAL;
1729         if (get_user(val, (int __user *)optval))
1730                 return -EFAULT;
1731
1732         lock_sock(sk);
1733         switch (optname) {
1734         case TCP_ULP:
1735         case TCP_FASTOPEN:
1736         case TCP_FASTOPEN_CONNECT:
1737         case TCP_FASTOPEN_KEY:
1738         case TCP_FASTOPEN_NO_COOKIE:
1739                 /* option not supported by SMC */
1740                 if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
1741                         smc_switch_to_fallback(smc);
1742                         smc->fallback_rsn = SMC_CLC_DECL_OPTUNSUPP;
1743                 } else {
1744                         if (!smc->use_fallback)
1745                                 rc = -EINVAL;
1746                 }
1747                 break;
1748         case TCP_NODELAY:
1749                 if (sk->sk_state != SMC_INIT &&
1750                     sk->sk_state != SMC_LISTEN &&
1751                     sk->sk_state != SMC_CLOSED) {
1752                         if (val && !smc->use_fallback)
1753                                 mod_delayed_work(system_wq, &smc->conn.tx_work,
1754                                                  0);
1755                 }
1756                 break;
1757         case TCP_CORK:
1758                 if (sk->sk_state != SMC_INIT &&
1759                     sk->sk_state != SMC_LISTEN &&
1760                     sk->sk_state != SMC_CLOSED) {
1761                         if (!val && !smc->use_fallback)
1762                                 mod_delayed_work(system_wq, &smc->conn.tx_work,
1763                                                  0);
1764                 }
1765                 break;
1766         case TCP_DEFER_ACCEPT:
1767                 smc->sockopt_defer_accept = val;
1768                 break;
1769         default:
1770                 break;
1771         }
1772         release_sock(sk);
1773
1774         return rc;
1775 }
1776
1777 static int smc_getsockopt(struct socket *sock, int level, int optname,
1778                           char __user *optval, int __user *optlen)
1779 {
1780         struct smc_sock *smc;
1781
1782         smc = smc_sk(sock->sk);
1783         /* socket options apply to the CLC socket */
1784         return smc->clcsock->ops->getsockopt(smc->clcsock, level, optname,
1785                                              optval, optlen);
1786 }
1787
1788 static int smc_ioctl(struct socket *sock, unsigned int cmd,
1789                      unsigned long arg)
1790 {
1791         union smc_host_cursor cons, urg;
1792         struct smc_connection *conn;
1793         struct smc_sock *smc;
1794         int answ;
1795
1796         smc = smc_sk(sock->sk);
1797         conn = &smc->conn;
1798         lock_sock(&smc->sk);
1799         if (smc->use_fallback) {
1800                 if (!smc->clcsock) {
1801                         release_sock(&smc->sk);
1802                         return -EBADF;
1803                 }
1804                 answ = smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg);
1805                 release_sock(&smc->sk);
1806                 return answ;
1807         }
1808         switch (cmd) {
1809         case SIOCINQ: /* same as FIONREAD */
1810                 if (smc->sk.sk_state == SMC_LISTEN) {
1811                         release_sock(&smc->sk);
1812                         return -EINVAL;
1813                 }
1814                 if (smc->sk.sk_state == SMC_INIT ||
1815                     smc->sk.sk_state == SMC_CLOSED)
1816                         answ = 0;
1817                 else
1818                         answ = atomic_read(&smc->conn.bytes_to_rcv);
1819                 break;
1820         case SIOCOUTQ:
1821                 /* output queue size (not send + not acked) */
1822                 if (smc->sk.sk_state == SMC_LISTEN) {
1823                         release_sock(&smc->sk);
1824                         return -EINVAL;
1825                 }
1826                 if (smc->sk.sk_state == SMC_INIT ||
1827                     smc->sk.sk_state == SMC_CLOSED)
1828                         answ = 0;
1829                 else
1830                         answ = smc->conn.sndbuf_desc->len -
1831                                         atomic_read(&smc->conn.sndbuf_space);
1832                 break;
1833         case SIOCOUTQNSD:
1834                 /* output queue size (not send only) */
1835                 if (smc->sk.sk_state == SMC_LISTEN) {
1836                         release_sock(&smc->sk);
1837                         return -EINVAL;
1838                 }
1839                 if (smc->sk.sk_state == SMC_INIT ||
1840                     smc->sk.sk_state == SMC_CLOSED)
1841                         answ = 0;
1842                 else
1843                         answ = smc_tx_prepared_sends(&smc->conn);
1844                 break;
1845         case SIOCATMARK:
1846                 if (smc->sk.sk_state == SMC_LISTEN) {
1847                         release_sock(&smc->sk);
1848                         return -EINVAL;
1849                 }
1850                 if (smc->sk.sk_state == SMC_INIT ||
1851                     smc->sk.sk_state == SMC_CLOSED) {
1852                         answ = 0;
1853                 } else {
1854                         smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
1855                         smc_curs_copy(&urg, &conn->urg_curs, conn);
1856                         answ = smc_curs_diff(conn->rmb_desc->len,
1857                                              &cons, &urg) == 1;
1858                 }
1859                 break;
1860         default:
1861                 release_sock(&smc->sk);
1862                 return -ENOIOCTLCMD;
1863         }
1864         release_sock(&smc->sk);
1865
1866         return put_user(answ, (int __user *)arg);
1867 }
1868
1869 static ssize_t smc_sendpage(struct socket *sock, struct page *page,
1870                             int offset, size_t size, int flags)
1871 {
1872         struct sock *sk = sock->sk;
1873         struct smc_sock *smc;
1874         int rc = -EPIPE;
1875
1876         smc = smc_sk(sk);
1877         lock_sock(sk);
1878         if (sk->sk_state != SMC_ACTIVE) {
1879                 release_sock(sk);
1880                 goto out;
1881         }
1882         release_sock(sk);
1883         if (smc->use_fallback)
1884                 rc = kernel_sendpage(smc->clcsock, page, offset,
1885                                      size, flags);
1886         else
1887                 rc = sock_no_sendpage(sock, page, offset, size, flags);
1888
1889 out:
1890         return rc;
1891 }
1892
1893 /* Map the affected portions of the rmbe into an spd, note the number of bytes
1894  * to splice in conn->splice_pending, and press 'go'. Delays consumer cursor
1895  * updates till whenever a respective page has been fully processed.
1896  * Note that subsequent recv() calls have to wait till all splice() processing
1897  * completed.
1898  */
1899 static ssize_t smc_splice_read(struct socket *sock, loff_t *ppos,
1900                                struct pipe_inode_info *pipe, size_t len,
1901                                unsigned int flags)
1902 {
1903         struct sock *sk = sock->sk;
1904         struct smc_sock *smc;
1905         int rc = -ENOTCONN;
1906
1907         smc = smc_sk(sk);
1908         lock_sock(sk);
1909         if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
1910                 /* socket was connected before, no more data to read */
1911                 rc = 0;
1912                 goto out;
1913         }
1914         if (sk->sk_state == SMC_INIT ||
1915             sk->sk_state == SMC_LISTEN ||
1916             sk->sk_state == SMC_CLOSED)
1917                 goto out;
1918
1919         if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
1920                 rc = 0;
1921                 goto out;
1922         }
1923
1924         if (smc->use_fallback) {
1925                 rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos,
1926                                                     pipe, len, flags);
1927         } else {
1928                 if (*ppos) {
1929                         rc = -ESPIPE;
1930                         goto out;
1931                 }
1932                 if (flags & SPLICE_F_NONBLOCK)
1933                         flags = MSG_DONTWAIT;
1934                 else
1935                         flags = 0;
1936                 rc = smc_rx_recvmsg(smc, NULL, pipe, len, flags);
1937         }
1938 out:
1939         release_sock(sk);
1940
1941         return rc;
1942 }
1943
1944 /* must look like tcp */
1945 static const struct proto_ops smc_sock_ops = {
1946         .family         = PF_SMC,
1947         .owner          = THIS_MODULE,
1948         .release        = smc_release,
1949         .bind           = smc_bind,
1950         .connect        = smc_connect,
1951         .socketpair     = sock_no_socketpair,
1952         .accept         = smc_accept,
1953         .getname        = smc_getname,
1954         .poll           = smc_poll,
1955         .ioctl          = smc_ioctl,
1956         .listen         = smc_listen,
1957         .shutdown       = smc_shutdown,
1958         .setsockopt     = smc_setsockopt,
1959         .getsockopt     = smc_getsockopt,
1960         .sendmsg        = smc_sendmsg,
1961         .recvmsg        = smc_recvmsg,
1962         .mmap           = sock_no_mmap,
1963         .sendpage       = smc_sendpage,
1964         .splice_read    = smc_splice_read,
1965 };
1966
1967 static int smc_create(struct net *net, struct socket *sock, int protocol,
1968                       int kern)
1969 {
1970         int family = (protocol == SMCPROTO_SMC6) ? PF_INET6 : PF_INET;
1971         struct smc_sock *smc;
1972         struct sock *sk;
1973         int rc;
1974
1975         rc = -ESOCKTNOSUPPORT;
1976         if (sock->type != SOCK_STREAM)
1977                 goto out;
1978
1979         rc = -EPROTONOSUPPORT;
1980         if (protocol != SMCPROTO_SMC && protocol != SMCPROTO_SMC6)
1981                 goto out;
1982
1983         rc = -ENOBUFS;
1984         sock->ops = &smc_sock_ops;
1985         sk = smc_sock_alloc(net, sock, protocol);
1986         if (!sk)
1987                 goto out;
1988
1989         /* create internal TCP socket for CLC handshake and fallback */
1990         smc = smc_sk(sk);
1991         smc->use_fallback = false; /* assume rdma capability first */
1992         smc->fallback_rsn = 0;
1993         rc = sock_create_kern(net, family, SOCK_STREAM, IPPROTO_TCP,
1994                               &smc->clcsock);
1995         if (rc) {
1996                 sk_common_release(sk);
1997                 goto out;
1998         }
1999         smc->sk.sk_sndbuf = max(smc->clcsock->sk->sk_sndbuf, SMC_BUF_MIN_SIZE);
2000         smc->sk.sk_rcvbuf = max(smc->clcsock->sk->sk_rcvbuf, SMC_BUF_MIN_SIZE);
2001
2002 out:
2003         return rc;
2004 }
2005
2006 static const struct net_proto_family smc_sock_family_ops = {
2007         .family = PF_SMC,
2008         .owner  = THIS_MODULE,
2009         .create = smc_create,
2010 };
2011
2012 unsigned int smc_net_id;
2013
2014 static __net_init int smc_net_init(struct net *net)
2015 {
2016         return smc_pnet_net_init(net);
2017 }
2018
2019 static void __net_exit smc_net_exit(struct net *net)
2020 {
2021         smc_pnet_net_exit(net);
2022 }
2023
2024 static struct pernet_operations smc_net_ops = {
2025         .init = smc_net_init,
2026         .exit = smc_net_exit,
2027         .id   = &smc_net_id,
2028         .size = sizeof(struct smc_net),
2029 };
2030
2031 static int __init smc_init(void)
2032 {
2033         int rc;
2034
2035         rc = register_pernet_subsys(&smc_net_ops);
2036         if (rc)
2037                 return rc;
2038
2039         rc = smc_pnet_init();
2040         if (rc)
2041                 goto out_pernet_subsys;
2042
2043         rc = smc_core_init();
2044         if (rc) {
2045                 pr_err("%s: smc_core_init fails with %d\n", __func__, rc);
2046                 goto out_pnet;
2047         }
2048
2049         rc = smc_llc_init();
2050         if (rc) {
2051                 pr_err("%s: smc_llc_init fails with %d\n", __func__, rc);
2052                 goto out_core;
2053         }
2054
2055         rc = smc_cdc_init();
2056         if (rc) {
2057                 pr_err("%s: smc_cdc_init fails with %d\n", __func__, rc);
2058                 goto out_core;
2059         }
2060
2061         rc = proto_register(&smc_proto, 1);
2062         if (rc) {
2063                 pr_err("%s: proto_register(v4) fails with %d\n", __func__, rc);
2064                 goto out_core;
2065         }
2066
2067         rc = proto_register(&smc_proto6, 1);
2068         if (rc) {
2069                 pr_err("%s: proto_register(v6) fails with %d\n", __func__, rc);
2070                 goto out_proto;
2071         }
2072
2073         rc = sock_register(&smc_sock_family_ops);
2074         if (rc) {
2075                 pr_err("%s: sock_register fails with %d\n", __func__, rc);
2076                 goto out_proto6;
2077         }
2078         INIT_HLIST_HEAD(&smc_v4_hashinfo.ht);
2079         INIT_HLIST_HEAD(&smc_v6_hashinfo.ht);
2080
2081         rc = smc_ib_register_client();
2082         if (rc) {
2083                 pr_err("%s: ib_register fails with %d\n", __func__, rc);
2084                 goto out_sock;
2085         }
2086
2087         static_branch_enable(&tcp_have_smc);
2088         return 0;
2089
2090 out_sock:
2091         sock_unregister(PF_SMC);
2092 out_proto6:
2093         proto_unregister(&smc_proto6);
2094 out_proto:
2095         proto_unregister(&smc_proto);
2096 out_core:
2097         smc_core_exit();
2098 out_pnet:
2099         smc_pnet_exit();
2100 out_pernet_subsys:
2101         unregister_pernet_subsys(&smc_net_ops);
2102
2103         return rc;
2104 }
2105
2106 static void __exit smc_exit(void)
2107 {
2108         static_branch_disable(&tcp_have_smc);
2109         sock_unregister(PF_SMC);
2110         smc_core_exit();
2111         smc_ib_unregister_client();
2112         proto_unregister(&smc_proto6);
2113         proto_unregister(&smc_proto);
2114         smc_pnet_exit();
2115         unregister_pernet_subsys(&smc_net_ops);
2116         rcu_barrier();
2117 }
2118
2119 module_init(smc_init);
2120 module_exit(smc_exit);
2121
2122 MODULE_AUTHOR("Ursula Braun <ubraun@linux.vnet.ibm.com>");
2123 MODULE_DESCRIPTION("smc socket address family");
2124 MODULE_LICENSE("GPL");
2125 MODULE_ALIAS_NETPROTO(PF_SMC);