1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Shared Memory Communications over RDMA (SMC-R) and RoCE 4 * 5 * Basic Transport Functions exploiting Infiniband API 6 * 7 * Copyright IBM Corp. 2016 8 * 9 * Author(s): Ursula Braun <ubraun@linux.vnet.ibm.com> 10 */ 11 12 #include <linux/socket.h> 13 #include <linux/if_vlan.h> 14 #include <linux/random.h> 15 #include <linux/workqueue.h> 16 #include <net/tcp.h> 17 #include <net/sock.h> 18 #include <rdma/ib_verbs.h> 19 #include <rdma/ib_cache.h> 20 21 #include "smc.h" 22 #include "smc_clc.h" 23 #include "smc_core.h" 24 #include "smc_ib.h" 25 #include "smc_wr.h" 26 #include "smc_llc.h" 27 #include "smc_cdc.h" 28 #include "smc_close.h" 29 #include "smc_ism.h" 30 31 #define SMC_LGR_NUM_INCR 256 32 #define SMC_LGR_FREE_DELAY_SERV (600 * HZ) 33 #define SMC_LGR_FREE_DELAY_CLNT (SMC_LGR_FREE_DELAY_SERV + 10 * HZ) 34 #define SMC_LGR_FREE_DELAY_FAST (8 * HZ) 35 36 static struct smc_lgr_list smc_lgr_list = { /* established link groups */ 37 .lock = __SPIN_LOCK_UNLOCKED(smc_lgr_list.lock), 38 .list = LIST_HEAD_INIT(smc_lgr_list.list), 39 .num = 0, 40 }; 41 42 static void smc_buf_free(struct smc_link_group *lgr, bool is_rmb, 43 struct smc_buf_desc *buf_desc); 44 45 static void smc_lgr_schedule_free_work(struct smc_link_group *lgr) 46 { 47 /* client link group creation always follows the server link group 48 * creation. For client use a somewhat higher removal delay time, 49 * otherwise there is a risk of out-of-sync link groups. 50 */ 51 mod_delayed_work(system_wq, &lgr->free_work, 52 (!lgr->is_smcd && lgr->role == SMC_CLNT) ? 53 SMC_LGR_FREE_DELAY_CLNT : SMC_LGR_FREE_DELAY_SERV); 54 } 55 56 void smc_lgr_schedule_free_work_fast(struct smc_link_group *lgr) 57 { 58 mod_delayed_work(system_wq, &lgr->free_work, SMC_LGR_FREE_DELAY_FAST); 59 } 60 61 /* Register connection's alert token in our lookup structure. 62 * To use rbtrees we have to implement our own insert core. 63 * Requires @conns_lock 64 * @smc connection to register 65 * Returns 0 on success, != otherwise. 66 */ 67 static void smc_lgr_add_alert_token(struct smc_connection *conn) 68 { 69 struct rb_node **link, *parent = NULL; 70 u32 token = conn->alert_token_local; 71 72 link = &conn->lgr->conns_all.rb_node; 73 while (*link) { 74 struct smc_connection *cur = rb_entry(*link, 75 struct smc_connection, alert_node); 76 77 parent = *link; 78 if (cur->alert_token_local > token) 79 link = &parent->rb_left; 80 else 81 link = &parent->rb_right; 82 } 83 /* Put the new node there */ 84 rb_link_node(&conn->alert_node, parent, link); 85 rb_insert_color(&conn->alert_node, &conn->lgr->conns_all); 86 } 87 88 /* Register connection in link group by assigning an alert token 89 * registered in a search tree. 90 * Requires @conns_lock 91 * Note that '0' is a reserved value and not assigned. 92 */ 93 static void smc_lgr_register_conn(struct smc_connection *conn) 94 { 95 struct smc_sock *smc = container_of(conn, struct smc_sock, conn); 96 static atomic_t nexttoken = ATOMIC_INIT(0); 97 98 /* find a new alert_token_local value not yet used by some connection 99 * in this link group 100 */ 101 sock_hold(&smc->sk); /* sock_put in smc_lgr_unregister_conn() */ 102 while (!conn->alert_token_local) { 103 conn->alert_token_local = atomic_inc_return(&nexttoken); 104 if (smc_lgr_find_conn(conn->alert_token_local, conn->lgr)) 105 conn->alert_token_local = 0; 106 } 107 smc_lgr_add_alert_token(conn); 108 conn->lgr->conns_num++; 109 } 110 111 /* Unregister connection and reset the alert token of the given connection< 112 */ 113 static void __smc_lgr_unregister_conn(struct smc_connection *conn) 114 { 115 struct smc_sock *smc = container_of(conn, struct smc_sock, conn); 116 struct smc_link_group *lgr = conn->lgr; 117 118 rb_erase(&conn->alert_node, &lgr->conns_all); 119 lgr->conns_num--; 120 conn->alert_token_local = 0; 121 sock_put(&smc->sk); /* sock_hold in smc_lgr_register_conn() */ 122 } 123 124 /* Unregister connection from lgr 125 */ 126 static void smc_lgr_unregister_conn(struct smc_connection *conn) 127 { 128 struct smc_link_group *lgr = conn->lgr; 129 130 if (!lgr) 131 return; 132 write_lock_bh(&lgr->conns_lock); 133 if (conn->alert_token_local) { 134 __smc_lgr_unregister_conn(conn); 135 } 136 write_unlock_bh(&lgr->conns_lock); 137 } 138 139 /* Send delete link, either as client to request the initiation 140 * of the DELETE LINK sequence from server; or as server to 141 * initiate the delete processing. See smc_llc_rx_delete_link(). 142 */ 143 static int smc_link_send_delete(struct smc_link *lnk) 144 { 145 if (lnk->state == SMC_LNK_ACTIVE && 146 !smc_llc_send_delete_link(lnk, SMC_LLC_REQ, true)) { 147 smc_llc_link_deleting(lnk); 148 return 0; 149 } 150 return -ENOTCONN; 151 } 152 153 static void smc_lgr_free(struct smc_link_group *lgr); 154 155 static void smc_lgr_free_work(struct work_struct *work) 156 { 157 struct smc_link_group *lgr = container_of(to_delayed_work(work), 158 struct smc_link_group, 159 free_work); 160 bool conns; 161 162 spin_lock_bh(&smc_lgr_list.lock); 163 read_lock_bh(&lgr->conns_lock); 164 conns = RB_EMPTY_ROOT(&lgr->conns_all); 165 read_unlock_bh(&lgr->conns_lock); 166 if (!conns) { /* number of lgr connections is no longer zero */ 167 spin_unlock_bh(&smc_lgr_list.lock); 168 return; 169 } 170 if (!list_empty(&lgr->list)) 171 list_del_init(&lgr->list); /* remove from smc_lgr_list */ 172 spin_unlock_bh(&smc_lgr_list.lock); 173 174 if (!lgr->is_smcd && !lgr->terminating) { 175 struct smc_link *lnk = &lgr->lnk[SMC_SINGLE_LINK]; 176 177 /* try to send del link msg, on error free lgr immediately */ 178 if (lnk->state == SMC_LNK_ACTIVE && 179 !smc_link_send_delete(lnk)) { 180 /* reschedule in case we never receive a response */ 181 smc_lgr_schedule_free_work(lgr); 182 return; 183 } 184 } 185 186 if (!delayed_work_pending(&lgr->free_work)) { 187 struct smc_link *lnk = &lgr->lnk[SMC_SINGLE_LINK]; 188 189 if (!lgr->is_smcd && lnk->state != SMC_LNK_INACTIVE) 190 smc_llc_link_inactive(lnk); 191 if (lgr->is_smcd) 192 smc_ism_signal_shutdown(lgr); 193 smc_lgr_free(lgr); 194 } 195 } 196 197 /* create a new SMC link group */ 198 static int smc_lgr_create(struct smc_sock *smc, struct smc_init_info *ini) 199 { 200 struct smc_link_group *lgr; 201 struct smc_link *lnk; 202 u8 rndvec[3]; 203 int rc = 0; 204 int i; 205 206 if (ini->is_smcd && ini->vlan_id) { 207 if (smc_ism_get_vlan(ini->ism_dev, ini->vlan_id)) { 208 rc = SMC_CLC_DECL_ISMVLANERR; 209 goto out; 210 } 211 } 212 213 lgr = kzalloc(sizeof(*lgr), GFP_KERNEL); 214 if (!lgr) { 215 rc = SMC_CLC_DECL_MEM; 216 goto out; 217 } 218 lgr->is_smcd = ini->is_smcd; 219 lgr->sync_err = 0; 220 lgr->vlan_id = ini->vlan_id; 221 rwlock_init(&lgr->sndbufs_lock); 222 rwlock_init(&lgr->rmbs_lock); 223 rwlock_init(&lgr->conns_lock); 224 for (i = 0; i < SMC_RMBE_SIZES; i++) { 225 INIT_LIST_HEAD(&lgr->sndbufs[i]); 226 INIT_LIST_HEAD(&lgr->rmbs[i]); 227 } 228 smc_lgr_list.num += SMC_LGR_NUM_INCR; 229 memcpy(&lgr->id, (u8 *)&smc_lgr_list.num, SMC_LGR_ID_SIZE); 230 INIT_DELAYED_WORK(&lgr->free_work, smc_lgr_free_work); 231 lgr->conns_all = RB_ROOT; 232 if (ini->is_smcd) { 233 /* SMC-D specific settings */ 234 lgr->peer_gid = ini->ism_gid; 235 lgr->smcd = ini->ism_dev; 236 } else { 237 /* SMC-R specific settings */ 238 lgr->role = smc->listen_smc ? SMC_SERV : SMC_CLNT; 239 memcpy(lgr->peer_systemid, ini->ib_lcl->id_for_peer, 240 SMC_SYSTEMID_LEN); 241 242 lnk = &lgr->lnk[SMC_SINGLE_LINK]; 243 /* initialize link */ 244 lnk->state = SMC_LNK_ACTIVATING; 245 lnk->link_id = SMC_SINGLE_LINK; 246 lnk->smcibdev = ini->ib_dev; 247 lnk->ibport = ini->ib_port; 248 lnk->path_mtu = 249 ini->ib_dev->pattr[ini->ib_port - 1].active_mtu; 250 if (!ini->ib_dev->initialized) 251 smc_ib_setup_per_ibdev(ini->ib_dev); 252 get_random_bytes(rndvec, sizeof(rndvec)); 253 lnk->psn_initial = rndvec[0] + (rndvec[1] << 8) + 254 (rndvec[2] << 16); 255 rc = smc_ib_determine_gid(lnk->smcibdev, lnk->ibport, 256 ini->vlan_id, lnk->gid, 257 &lnk->sgid_index); 258 if (rc) 259 goto free_lgr; 260 rc = smc_llc_link_init(lnk); 261 if (rc) 262 goto free_lgr; 263 rc = smc_wr_alloc_link_mem(lnk); 264 if (rc) 265 goto clear_llc_lnk; 266 rc = smc_ib_create_protection_domain(lnk); 267 if (rc) 268 goto free_link_mem; 269 rc = smc_ib_create_queue_pair(lnk); 270 if (rc) 271 goto dealloc_pd; 272 rc = smc_wr_create_link(lnk); 273 if (rc) 274 goto destroy_qp; 275 } 276 smc->conn.lgr = lgr; 277 spin_lock_bh(&smc_lgr_list.lock); 278 list_add(&lgr->list, &smc_lgr_list.list); 279 spin_unlock_bh(&smc_lgr_list.lock); 280 return 0; 281 282 destroy_qp: 283 smc_ib_destroy_queue_pair(lnk); 284 dealloc_pd: 285 smc_ib_dealloc_protection_domain(lnk); 286 free_link_mem: 287 smc_wr_free_link_mem(lnk); 288 clear_llc_lnk: 289 smc_llc_link_clear(lnk); 290 free_lgr: 291 kfree(lgr); 292 out: 293 if (rc < 0) { 294 if (rc == -ENOMEM) 295 rc = SMC_CLC_DECL_MEM; 296 else 297 rc = SMC_CLC_DECL_INTERR; 298 } 299 return rc; 300 } 301 302 static void smc_buf_unuse(struct smc_connection *conn, 303 struct smc_link_group *lgr) 304 { 305 if (conn->sndbuf_desc) 306 conn->sndbuf_desc->used = 0; 307 if (conn->rmb_desc) { 308 if (!conn->rmb_desc->regerr) { 309 if (!lgr->is_smcd) { 310 /* unregister rmb with peer */ 311 smc_llc_do_delete_rkey( 312 &lgr->lnk[SMC_SINGLE_LINK], 313 conn->rmb_desc); 314 } 315 conn->rmb_desc->used = 0; 316 } else { 317 /* buf registration failed, reuse not possible */ 318 write_lock_bh(&lgr->rmbs_lock); 319 list_del(&conn->rmb_desc->list); 320 write_unlock_bh(&lgr->rmbs_lock); 321 322 smc_buf_free(lgr, true, conn->rmb_desc); 323 } 324 } 325 } 326 327 /* remove a finished connection from its link group */ 328 void smc_conn_free(struct smc_connection *conn) 329 { 330 struct smc_link_group *lgr = conn->lgr; 331 332 if (!lgr) 333 return; 334 if (lgr->is_smcd) { 335 smc_ism_unset_conn(conn); 336 tasklet_kill(&conn->rx_tsklet); 337 } else { 338 smc_cdc_tx_dismiss_slots(conn); 339 } 340 smc_lgr_unregister_conn(conn); 341 smc_buf_unuse(conn, lgr); /* allow buffer reuse */ 342 conn->lgr = NULL; 343 344 if (!lgr->conns_num) 345 smc_lgr_schedule_free_work(lgr); 346 } 347 348 static void smc_link_clear(struct smc_link *lnk) 349 { 350 lnk->peer_qpn = 0; 351 smc_llc_link_clear(lnk); 352 smc_ib_modify_qp_reset(lnk); 353 smc_wr_free_link(lnk); 354 smc_ib_destroy_queue_pair(lnk); 355 smc_ib_dealloc_protection_domain(lnk); 356 smc_wr_free_link_mem(lnk); 357 } 358 359 static void smcr_buf_free(struct smc_link_group *lgr, bool is_rmb, 360 struct smc_buf_desc *buf_desc) 361 { 362 struct smc_link *lnk = &lgr->lnk[SMC_SINGLE_LINK]; 363 364 if (is_rmb) { 365 if (buf_desc->mr_rx[SMC_SINGLE_LINK]) 366 smc_ib_put_memory_region( 367 buf_desc->mr_rx[SMC_SINGLE_LINK]); 368 smc_ib_buf_unmap_sg(lnk->smcibdev, buf_desc, 369 DMA_FROM_DEVICE); 370 } else { 371 smc_ib_buf_unmap_sg(lnk->smcibdev, buf_desc, 372 DMA_TO_DEVICE); 373 } 374 sg_free_table(&buf_desc->sgt[SMC_SINGLE_LINK]); 375 if (buf_desc->pages) 376 __free_pages(buf_desc->pages, buf_desc->order); 377 kfree(buf_desc); 378 } 379 380 static void smcd_buf_free(struct smc_link_group *lgr, bool is_dmb, 381 struct smc_buf_desc *buf_desc) 382 { 383 if (is_dmb) { 384 /* restore original buf len */ 385 buf_desc->len += sizeof(struct smcd_cdc_msg); 386 smc_ism_unregister_dmb(lgr->smcd, buf_desc); 387 } else { 388 kfree(buf_desc->cpu_addr); 389 } 390 kfree(buf_desc); 391 } 392 393 static void smc_buf_free(struct smc_link_group *lgr, bool is_rmb, 394 struct smc_buf_desc *buf_desc) 395 { 396 if (lgr->is_smcd) 397 smcd_buf_free(lgr, is_rmb, buf_desc); 398 else 399 smcr_buf_free(lgr, is_rmb, buf_desc); 400 } 401 402 static void __smc_lgr_free_bufs(struct smc_link_group *lgr, bool is_rmb) 403 { 404 struct smc_buf_desc *buf_desc, *bf_desc; 405 struct list_head *buf_list; 406 int i; 407 408 for (i = 0; i < SMC_RMBE_SIZES; i++) { 409 if (is_rmb) 410 buf_list = &lgr->rmbs[i]; 411 else 412 buf_list = &lgr->sndbufs[i]; 413 list_for_each_entry_safe(buf_desc, bf_desc, buf_list, 414 list) { 415 list_del(&buf_desc->list); 416 smc_buf_free(lgr, is_rmb, buf_desc); 417 } 418 } 419 } 420 421 static void smc_lgr_free_bufs(struct smc_link_group *lgr) 422 { 423 /* free send buffers */ 424 __smc_lgr_free_bufs(lgr, false); 425 /* free rmbs */ 426 __smc_lgr_free_bufs(lgr, true); 427 } 428 429 /* remove a link group */ 430 static void smc_lgr_free(struct smc_link_group *lgr) 431 { 432 smc_lgr_free_bufs(lgr); 433 if (lgr->is_smcd) 434 smc_ism_put_vlan(lgr->smcd, lgr->vlan_id); 435 else 436 smc_link_clear(&lgr->lnk[SMC_SINGLE_LINK]); 437 kfree(lgr); 438 } 439 440 void smc_lgr_forget(struct smc_link_group *lgr) 441 { 442 spin_lock_bh(&smc_lgr_list.lock); 443 /* do not use this link group for new connections */ 444 if (!list_empty(&lgr->list)) 445 list_del_init(&lgr->list); 446 spin_unlock_bh(&smc_lgr_list.lock); 447 } 448 449 /* terminate linkgroup abnormally */ 450 static void __smc_lgr_terminate(struct smc_link_group *lgr) 451 { 452 struct smc_connection *conn; 453 struct smc_sock *smc; 454 struct rb_node *node; 455 456 if (lgr->terminating) 457 return; /* lgr already terminating */ 458 lgr->terminating = 1; 459 if (!list_empty(&lgr->list)) /* forget lgr */ 460 list_del_init(&lgr->list); 461 if (!lgr->is_smcd) 462 smc_llc_link_inactive(&lgr->lnk[SMC_SINGLE_LINK]); 463 464 write_lock_bh(&lgr->conns_lock); 465 node = rb_first(&lgr->conns_all); 466 while (node) { 467 conn = rb_entry(node, struct smc_connection, alert_node); 468 smc = container_of(conn, struct smc_sock, conn); 469 sock_hold(&smc->sk); /* sock_put in close work */ 470 conn->local_tx_ctrl.conn_state_flags.peer_conn_abort = 1; 471 __smc_lgr_unregister_conn(conn); 472 conn->lgr = NULL; 473 write_unlock_bh(&lgr->conns_lock); 474 if (!schedule_work(&conn->close_work)) 475 sock_put(&smc->sk); 476 write_lock_bh(&lgr->conns_lock); 477 node = rb_first(&lgr->conns_all); 478 } 479 write_unlock_bh(&lgr->conns_lock); 480 if (!lgr->is_smcd) 481 wake_up(&lgr->lnk[SMC_SINGLE_LINK].wr_reg_wait); 482 smc_lgr_schedule_free_work(lgr); 483 } 484 485 void smc_lgr_terminate(struct smc_link_group *lgr) 486 { 487 spin_lock_bh(&smc_lgr_list.lock); 488 __smc_lgr_terminate(lgr); 489 spin_unlock_bh(&smc_lgr_list.lock); 490 } 491 492 /* Called when IB port is terminated */ 493 void smc_port_terminate(struct smc_ib_device *smcibdev, u8 ibport) 494 { 495 struct smc_link_group *lgr, *l; 496 497 spin_lock_bh(&smc_lgr_list.lock); 498 list_for_each_entry_safe(lgr, l, &smc_lgr_list.list, list) { 499 if (!lgr->is_smcd && 500 lgr->lnk[SMC_SINGLE_LINK].smcibdev == smcibdev && 501 lgr->lnk[SMC_SINGLE_LINK].ibport == ibport) 502 __smc_lgr_terminate(lgr); 503 } 504 spin_unlock_bh(&smc_lgr_list.lock); 505 } 506 507 /* Called when SMC-D device is terminated or peer is lost */ 508 void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid, unsigned short vlan) 509 { 510 struct smc_link_group *lgr, *l; 511 LIST_HEAD(lgr_free_list); 512 513 /* run common cleanup function and build free list */ 514 spin_lock_bh(&smc_lgr_list.lock); 515 list_for_each_entry_safe(lgr, l, &smc_lgr_list.list, list) { 516 if (lgr->is_smcd && lgr->smcd == dev && 517 (!peer_gid || lgr->peer_gid == peer_gid) && 518 (vlan == VLAN_VID_MASK || lgr->vlan_id == vlan)) { 519 __smc_lgr_terminate(lgr); 520 list_move(&lgr->list, &lgr_free_list); 521 } 522 } 523 spin_unlock_bh(&smc_lgr_list.lock); 524 525 /* cancel the regular free workers and actually free lgrs */ 526 list_for_each_entry_safe(lgr, l, &lgr_free_list, list) { 527 list_del_init(&lgr->list); 528 cancel_delayed_work_sync(&lgr->free_work); 529 if (!peer_gid && vlan == VLAN_VID_MASK) /* dev terminated? */ 530 smc_ism_signal_shutdown(lgr); 531 smc_lgr_free(lgr); 532 } 533 } 534 535 /* Determine vlan of internal TCP socket. 536 * @vlan_id: address to store the determined vlan id into 537 */ 538 int smc_vlan_by_tcpsk(struct socket *clcsock, struct smc_init_info *ini) 539 { 540 struct dst_entry *dst = sk_dst_get(clcsock->sk); 541 struct net_device *ndev; 542 int i, nest_lvl, rc = 0; 543 544 ini->vlan_id = 0; 545 if (!dst) { 546 rc = -ENOTCONN; 547 goto out; 548 } 549 if (!dst->dev) { 550 rc = -ENODEV; 551 goto out_rel; 552 } 553 554 ndev = dst->dev; 555 if (is_vlan_dev(ndev)) { 556 ini->vlan_id = vlan_dev_vlan_id(ndev); 557 goto out_rel; 558 } 559 560 rtnl_lock(); 561 nest_lvl = dev_get_nest_level(ndev); 562 for (i = 0; i < nest_lvl; i++) { 563 struct list_head *lower = &ndev->adj_list.lower; 564 565 if (list_empty(lower)) 566 break; 567 lower = lower->next; 568 ndev = (struct net_device *)netdev_lower_get_next(ndev, &lower); 569 if (is_vlan_dev(ndev)) { 570 ini->vlan_id = vlan_dev_vlan_id(ndev); 571 break; 572 } 573 } 574 rtnl_unlock(); 575 576 out_rel: 577 dst_release(dst); 578 out: 579 return rc; 580 } 581 582 static bool smcr_lgr_match(struct smc_link_group *lgr, 583 struct smc_clc_msg_local *lcl, 584 enum smc_lgr_role role, u32 clcqpn) 585 { 586 return !memcmp(lgr->peer_systemid, lcl->id_for_peer, 587 SMC_SYSTEMID_LEN) && 588 !memcmp(lgr->lnk[SMC_SINGLE_LINK].peer_gid, &lcl->gid, 589 SMC_GID_SIZE) && 590 !memcmp(lgr->lnk[SMC_SINGLE_LINK].peer_mac, lcl->mac, 591 sizeof(lcl->mac)) && 592 lgr->role == role && 593 (lgr->role == SMC_SERV || 594 lgr->lnk[SMC_SINGLE_LINK].peer_qpn == clcqpn); 595 } 596 597 static bool smcd_lgr_match(struct smc_link_group *lgr, 598 struct smcd_dev *smcismdev, u64 peer_gid) 599 { 600 return lgr->peer_gid == peer_gid && lgr->smcd == smcismdev; 601 } 602 603 /* create a new SMC connection (and a new link group if necessary) */ 604 int smc_conn_create(struct smc_sock *smc, struct smc_init_info *ini) 605 { 606 struct smc_connection *conn = &smc->conn; 607 struct smc_link_group *lgr; 608 enum smc_lgr_role role; 609 int rc = 0; 610 611 ini->cln_first_contact = SMC_FIRST_CONTACT; 612 role = smc->listen_smc ? SMC_SERV : SMC_CLNT; 613 if (role == SMC_CLNT && ini->srv_first_contact) 614 /* create new link group as well */ 615 goto create; 616 617 /* determine if an existing link group can be reused */ 618 spin_lock_bh(&smc_lgr_list.lock); 619 list_for_each_entry(lgr, &smc_lgr_list.list, list) { 620 write_lock_bh(&lgr->conns_lock); 621 if ((ini->is_smcd ? 622 smcd_lgr_match(lgr, ini->ism_dev, ini->ism_gid) : 623 smcr_lgr_match(lgr, ini->ib_lcl, role, ini->ib_clcqpn)) && 624 !lgr->sync_err && 625 lgr->vlan_id == ini->vlan_id && 626 (role == SMC_CLNT || 627 lgr->conns_num < SMC_RMBS_PER_LGR_MAX)) { 628 /* link group found */ 629 ini->cln_first_contact = SMC_REUSE_CONTACT; 630 conn->lgr = lgr; 631 smc_lgr_register_conn(conn); /* add smc conn to lgr */ 632 if (delayed_work_pending(&lgr->free_work)) 633 cancel_delayed_work(&lgr->free_work); 634 write_unlock_bh(&lgr->conns_lock); 635 break; 636 } 637 write_unlock_bh(&lgr->conns_lock); 638 } 639 spin_unlock_bh(&smc_lgr_list.lock); 640 641 if (role == SMC_CLNT && !ini->srv_first_contact && 642 ini->cln_first_contact == SMC_FIRST_CONTACT) { 643 /* Server reuses a link group, but Client wants to start 644 * a new one 645 * send out_of_sync decline, reason synchr. error 646 */ 647 return SMC_CLC_DECL_SYNCERR; 648 } 649 650 create: 651 if (ini->cln_first_contact == SMC_FIRST_CONTACT) { 652 rc = smc_lgr_create(smc, ini); 653 if (rc) 654 goto out; 655 lgr = conn->lgr; 656 write_lock_bh(&lgr->conns_lock); 657 smc_lgr_register_conn(conn); /* add smc conn to lgr */ 658 write_unlock_bh(&lgr->conns_lock); 659 } 660 conn->local_tx_ctrl.common.type = SMC_CDC_MSG_TYPE; 661 conn->local_tx_ctrl.len = SMC_WR_TX_SIZE; 662 conn->urg_state = SMC_URG_READ; 663 if (ini->is_smcd) { 664 conn->rx_off = sizeof(struct smcd_cdc_msg); 665 smcd_cdc_rx_init(conn); /* init tasklet for this conn */ 666 } 667 #ifndef KERNEL_HAS_ATOMIC64 668 spin_lock_init(&conn->acurs_lock); 669 #endif 670 671 out: 672 return rc; 673 } 674 675 /* convert the RMB size into the compressed notation - minimum 16K. 676 * In contrast to plain ilog2, this rounds towards the next power of 2, 677 * so the socket application gets at least its desired sndbuf / rcvbuf size. 678 */ 679 static u8 smc_compress_bufsize(int size) 680 { 681 u8 compressed; 682 683 if (size <= SMC_BUF_MIN_SIZE) 684 return 0; 685 686 size = (size - 1) >> 14; 687 compressed = ilog2(size) + 1; 688 if (compressed >= SMC_RMBE_SIZES) 689 compressed = SMC_RMBE_SIZES - 1; 690 return compressed; 691 } 692 693 /* convert the RMB size from compressed notation into integer */ 694 int smc_uncompress_bufsize(u8 compressed) 695 { 696 u32 size; 697 698 size = 0x00000001 << (((int)compressed) + 14); 699 return (int)size; 700 } 701 702 /* try to reuse a sndbuf or rmb description slot for a certain 703 * buffer size; if not available, return NULL 704 */ 705 static struct smc_buf_desc *smc_buf_get_slot(int compressed_bufsize, 706 rwlock_t *lock, 707 struct list_head *buf_list) 708 { 709 struct smc_buf_desc *buf_slot; 710 711 read_lock_bh(lock); 712 list_for_each_entry(buf_slot, buf_list, list) { 713 if (cmpxchg(&buf_slot->used, 0, 1) == 0) { 714 read_unlock_bh(lock); 715 return buf_slot; 716 } 717 } 718 read_unlock_bh(lock); 719 return NULL; 720 } 721 722 /* one of the conditions for announcing a receiver's current window size is 723 * that it "results in a minimum increase in the window size of 10% of the 724 * receive buffer space" [RFC7609] 725 */ 726 static inline int smc_rmb_wnd_update_limit(int rmbe_size) 727 { 728 return min_t(int, rmbe_size / 10, SOCK_MIN_SNDBUF / 2); 729 } 730 731 static struct smc_buf_desc *smcr_new_buf_create(struct smc_link_group *lgr, 732 bool is_rmb, int bufsize) 733 { 734 struct smc_buf_desc *buf_desc; 735 struct smc_link *lnk; 736 int rc; 737 738 /* try to alloc a new buffer */ 739 buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL); 740 if (!buf_desc) 741 return ERR_PTR(-ENOMEM); 742 743 buf_desc->order = get_order(bufsize); 744 buf_desc->pages = alloc_pages(GFP_KERNEL | __GFP_NOWARN | 745 __GFP_NOMEMALLOC | __GFP_COMP | 746 __GFP_NORETRY | __GFP_ZERO, 747 buf_desc->order); 748 if (!buf_desc->pages) { 749 kfree(buf_desc); 750 return ERR_PTR(-EAGAIN); 751 } 752 buf_desc->cpu_addr = (void *)page_address(buf_desc->pages); 753 754 /* build the sg table from the pages */ 755 lnk = &lgr->lnk[SMC_SINGLE_LINK]; 756 rc = sg_alloc_table(&buf_desc->sgt[SMC_SINGLE_LINK], 1, 757 GFP_KERNEL); 758 if (rc) { 759 smc_buf_free(lgr, is_rmb, buf_desc); 760 return ERR_PTR(rc); 761 } 762 sg_set_buf(buf_desc->sgt[SMC_SINGLE_LINK].sgl, 763 buf_desc->cpu_addr, bufsize); 764 765 /* map sg table to DMA address */ 766 rc = smc_ib_buf_map_sg(lnk->smcibdev, buf_desc, 767 is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE); 768 /* SMC protocol depends on mapping to one DMA address only */ 769 if (rc != 1) { 770 smc_buf_free(lgr, is_rmb, buf_desc); 771 return ERR_PTR(-EAGAIN); 772 } 773 774 /* create a new memory region for the RMB */ 775 if (is_rmb) { 776 rc = smc_ib_get_memory_region(lnk->roce_pd, 777 IB_ACCESS_REMOTE_WRITE | 778 IB_ACCESS_LOCAL_WRITE, 779 buf_desc); 780 if (rc) { 781 smc_buf_free(lgr, is_rmb, buf_desc); 782 return ERR_PTR(rc); 783 } 784 } 785 786 buf_desc->len = bufsize; 787 return buf_desc; 788 } 789 790 #define SMCD_DMBE_SIZES 7 /* 0 -> 16KB, 1 -> 32KB, .. 6 -> 1MB */ 791 792 static struct smc_buf_desc *smcd_new_buf_create(struct smc_link_group *lgr, 793 bool is_dmb, int bufsize) 794 { 795 struct smc_buf_desc *buf_desc; 796 int rc; 797 798 if (smc_compress_bufsize(bufsize) > SMCD_DMBE_SIZES) 799 return ERR_PTR(-EAGAIN); 800 801 /* try to alloc a new DMB */ 802 buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL); 803 if (!buf_desc) 804 return ERR_PTR(-ENOMEM); 805 if (is_dmb) { 806 rc = smc_ism_register_dmb(lgr, bufsize, buf_desc); 807 if (rc) { 808 kfree(buf_desc); 809 return ERR_PTR(-EAGAIN); 810 } 811 buf_desc->pages = virt_to_page(buf_desc->cpu_addr); 812 /* CDC header stored in buf. So, pretend it was smaller */ 813 buf_desc->len = bufsize - sizeof(struct smcd_cdc_msg); 814 } else { 815 buf_desc->cpu_addr = kzalloc(bufsize, GFP_KERNEL | 816 __GFP_NOWARN | __GFP_NORETRY | 817 __GFP_NOMEMALLOC); 818 if (!buf_desc->cpu_addr) { 819 kfree(buf_desc); 820 return ERR_PTR(-EAGAIN); 821 } 822 buf_desc->len = bufsize; 823 } 824 return buf_desc; 825 } 826 827 static int __smc_buf_create(struct smc_sock *smc, bool is_smcd, bool is_rmb) 828 { 829 struct smc_buf_desc *buf_desc = ERR_PTR(-ENOMEM); 830 struct smc_connection *conn = &smc->conn; 831 struct smc_link_group *lgr = conn->lgr; 832 struct list_head *buf_list; 833 int bufsize, bufsize_short; 834 int sk_buf_size; 835 rwlock_t *lock; 836 837 if (is_rmb) 838 /* use socket recv buffer size (w/o overhead) as start value */ 839 sk_buf_size = smc->sk.sk_rcvbuf / 2; 840 else 841 /* use socket send buffer size (w/o overhead) as start value */ 842 sk_buf_size = smc->sk.sk_sndbuf / 2; 843 844 for (bufsize_short = smc_compress_bufsize(sk_buf_size); 845 bufsize_short >= 0; bufsize_short--) { 846 847 if (is_rmb) { 848 lock = &lgr->rmbs_lock; 849 buf_list = &lgr->rmbs[bufsize_short]; 850 } else { 851 lock = &lgr->sndbufs_lock; 852 buf_list = &lgr->sndbufs[bufsize_short]; 853 } 854 bufsize = smc_uncompress_bufsize(bufsize_short); 855 if ((1 << get_order(bufsize)) > SG_MAX_SINGLE_ALLOC) 856 continue; 857 858 /* check for reusable slot in the link group */ 859 buf_desc = smc_buf_get_slot(bufsize_short, lock, buf_list); 860 if (buf_desc) { 861 memset(buf_desc->cpu_addr, 0, bufsize); 862 break; /* found reusable slot */ 863 } 864 865 if (is_smcd) 866 buf_desc = smcd_new_buf_create(lgr, is_rmb, bufsize); 867 else 868 buf_desc = smcr_new_buf_create(lgr, is_rmb, bufsize); 869 870 if (PTR_ERR(buf_desc) == -ENOMEM) 871 break; 872 if (IS_ERR(buf_desc)) 873 continue; 874 875 buf_desc->used = 1; 876 write_lock_bh(lock); 877 list_add(&buf_desc->list, buf_list); 878 write_unlock_bh(lock); 879 break; /* found */ 880 } 881 882 if (IS_ERR(buf_desc)) 883 return -ENOMEM; 884 885 if (is_rmb) { 886 conn->rmb_desc = buf_desc; 887 conn->rmbe_size_short = bufsize_short; 888 smc->sk.sk_rcvbuf = bufsize * 2; 889 atomic_set(&conn->bytes_to_rcv, 0); 890 conn->rmbe_update_limit = 891 smc_rmb_wnd_update_limit(buf_desc->len); 892 if (is_smcd) 893 smc_ism_set_conn(conn); /* map RMB/smcd_dev to conn */ 894 } else { 895 conn->sndbuf_desc = buf_desc; 896 smc->sk.sk_sndbuf = bufsize * 2; 897 atomic_set(&conn->sndbuf_space, bufsize); 898 } 899 return 0; 900 } 901 902 void smc_sndbuf_sync_sg_for_cpu(struct smc_connection *conn) 903 { 904 struct smc_link_group *lgr = conn->lgr; 905 906 if (!conn->lgr || conn->lgr->is_smcd) 907 return; 908 smc_ib_sync_sg_for_cpu(lgr->lnk[SMC_SINGLE_LINK].smcibdev, 909 conn->sndbuf_desc, DMA_TO_DEVICE); 910 } 911 912 void smc_sndbuf_sync_sg_for_device(struct smc_connection *conn) 913 { 914 struct smc_link_group *lgr = conn->lgr; 915 916 if (!conn->lgr || conn->lgr->is_smcd) 917 return; 918 smc_ib_sync_sg_for_device(lgr->lnk[SMC_SINGLE_LINK].smcibdev, 919 conn->sndbuf_desc, DMA_TO_DEVICE); 920 } 921 922 void smc_rmb_sync_sg_for_cpu(struct smc_connection *conn) 923 { 924 struct smc_link_group *lgr = conn->lgr; 925 926 if (!conn->lgr || conn->lgr->is_smcd) 927 return; 928 smc_ib_sync_sg_for_cpu(lgr->lnk[SMC_SINGLE_LINK].smcibdev, 929 conn->rmb_desc, DMA_FROM_DEVICE); 930 } 931 932 void smc_rmb_sync_sg_for_device(struct smc_connection *conn) 933 { 934 struct smc_link_group *lgr = conn->lgr; 935 936 if (!conn->lgr || conn->lgr->is_smcd) 937 return; 938 smc_ib_sync_sg_for_device(lgr->lnk[SMC_SINGLE_LINK].smcibdev, 939 conn->rmb_desc, DMA_FROM_DEVICE); 940 } 941 942 /* create the send and receive buffer for an SMC socket; 943 * receive buffers are called RMBs; 944 * (even though the SMC protocol allows more than one RMB-element per RMB, 945 * the Linux implementation uses just one RMB-element per RMB, i.e. uses an 946 * extra RMB for every connection in a link group 947 */ 948 int smc_buf_create(struct smc_sock *smc, bool is_smcd) 949 { 950 int rc; 951 952 /* create send buffer */ 953 rc = __smc_buf_create(smc, is_smcd, false); 954 if (rc) 955 return rc; 956 /* create rmb */ 957 rc = __smc_buf_create(smc, is_smcd, true); 958 if (rc) 959 smc_buf_free(smc->conn.lgr, false, smc->conn.sndbuf_desc); 960 return rc; 961 } 962 963 static inline int smc_rmb_reserve_rtoken_idx(struct smc_link_group *lgr) 964 { 965 int i; 966 967 for_each_clear_bit(i, lgr->rtokens_used_mask, SMC_RMBS_PER_LGR_MAX) { 968 if (!test_and_set_bit(i, lgr->rtokens_used_mask)) 969 return i; 970 } 971 return -ENOSPC; 972 } 973 974 /* add a new rtoken from peer */ 975 int smc_rtoken_add(struct smc_link_group *lgr, __be64 nw_vaddr, __be32 nw_rkey) 976 { 977 u64 dma_addr = be64_to_cpu(nw_vaddr); 978 u32 rkey = ntohl(nw_rkey); 979 int i; 980 981 for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) { 982 if ((lgr->rtokens[i][SMC_SINGLE_LINK].rkey == rkey) && 983 (lgr->rtokens[i][SMC_SINGLE_LINK].dma_addr == dma_addr) && 984 test_bit(i, lgr->rtokens_used_mask)) { 985 /* already in list */ 986 return i; 987 } 988 } 989 i = smc_rmb_reserve_rtoken_idx(lgr); 990 if (i < 0) 991 return i; 992 lgr->rtokens[i][SMC_SINGLE_LINK].rkey = rkey; 993 lgr->rtokens[i][SMC_SINGLE_LINK].dma_addr = dma_addr; 994 return i; 995 } 996 997 /* delete an rtoken */ 998 int smc_rtoken_delete(struct smc_link_group *lgr, __be32 nw_rkey) 999 { 1000 u32 rkey = ntohl(nw_rkey); 1001 int i; 1002 1003 for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) { 1004 if (lgr->rtokens[i][SMC_SINGLE_LINK].rkey == rkey && 1005 test_bit(i, lgr->rtokens_used_mask)) { 1006 lgr->rtokens[i][SMC_SINGLE_LINK].rkey = 0; 1007 lgr->rtokens[i][SMC_SINGLE_LINK].dma_addr = 0; 1008 1009 clear_bit(i, lgr->rtokens_used_mask); 1010 return 0; 1011 } 1012 } 1013 return -ENOENT; 1014 } 1015 1016 /* save rkey and dma_addr received from peer during clc handshake */ 1017 int smc_rmb_rtoken_handling(struct smc_connection *conn, 1018 struct smc_clc_msg_accept_confirm *clc) 1019 { 1020 conn->rtoken_idx = smc_rtoken_add(conn->lgr, clc->rmb_dma_addr, 1021 clc->rmb_rkey); 1022 if (conn->rtoken_idx < 0) 1023 return conn->rtoken_idx; 1024 return 0; 1025 } 1026 1027 /* Called (from smc_exit) when module is removed */ 1028 void smc_core_exit(void) 1029 { 1030 struct smc_link_group *lgr, *lg; 1031 LIST_HEAD(lgr_freeing_list); 1032 1033 spin_lock_bh(&smc_lgr_list.lock); 1034 if (!list_empty(&smc_lgr_list.list)) 1035 list_splice_init(&smc_lgr_list.list, &lgr_freeing_list); 1036 spin_unlock_bh(&smc_lgr_list.lock); 1037 list_for_each_entry_safe(lgr, lg, &lgr_freeing_list, list) { 1038 list_del_init(&lgr->list); 1039 if (!lgr->is_smcd) { 1040 struct smc_link *lnk = &lgr->lnk[SMC_SINGLE_LINK]; 1041 1042 if (lnk->state == SMC_LNK_ACTIVE) 1043 smc_llc_send_delete_link(lnk, SMC_LLC_REQ, 1044 false); 1045 smc_llc_link_inactive(lnk); 1046 } 1047 cancel_delayed_work_sync(&lgr->free_work); 1048 if (lgr->is_smcd) 1049 smc_ism_signal_shutdown(lgr); 1050 smc_lgr_free(lgr); /* free link group */ 1051 } 1052 } 1053