net/smc/af_smc.c

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