1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * RDMA Transport Layer 4 * 5 * Copyright (c) 2014 - 2018 ProfitBricks GmbH. All rights reserved. 6 * Copyright (c) 2018 - 2019 1&1 IONOS Cloud GmbH. All rights reserved. 7 * Copyright (c) 2019 - 2020 1&1 IONOS SE. All rights reserved. 8 */ 9 10 #undef pr_fmt 11 #define pr_fmt(fmt) KBUILD_MODNAME " L" __stringify(__LINE__) ": " fmt 12 13 #include <linux/module.h> 14 #include <linux/rculist.h> 15 #include <linux/random.h> 16 17 #include "rtrs-clt.h" 18 #include "rtrs-log.h" 19 20 #define RTRS_CONNECT_TIMEOUT_MS 30000 21 /* 22 * Wait a bit before trying to reconnect after a failure 23 * in order to give server time to finish clean up which 24 * leads to "false positives" failed reconnect attempts 25 */ 26 #define RTRS_RECONNECT_BACKOFF 1000 27 /* 28 * Wait for additional random time between 0 and 8 seconds 29 * before starting to reconnect to avoid clients reconnecting 30 * all at once in case of a major network outage 31 */ 32 #define RTRS_RECONNECT_SEED 8 33 34 #define FIRST_CONN 0x01 35 /* limit to 128 * 4k = 512k max IO */ 36 #define RTRS_MAX_SEGMENTS 128 37 38 MODULE_DESCRIPTION("RDMA Transport Client"); 39 MODULE_LICENSE("GPL"); 40 41 static const struct rtrs_rdma_dev_pd_ops dev_pd_ops; 42 static struct rtrs_rdma_dev_pd dev_pd = { 43 .ops = &dev_pd_ops 44 }; 45 46 static struct workqueue_struct *rtrs_wq; 47 static struct class *rtrs_clt_dev_class; 48 49 static inline bool rtrs_clt_is_connected(const struct rtrs_clt_sess *clt) 50 { 51 struct rtrs_clt_path *clt_path; 52 bool connected = false; 53 54 rcu_read_lock(); 55 list_for_each_entry_rcu(clt_path, &clt->paths_list, s.entry) 56 connected |= READ_ONCE(clt_path->state) == RTRS_CLT_CONNECTED; 57 rcu_read_unlock(); 58 59 return connected; 60 } 61 62 static struct rtrs_permit * 63 __rtrs_get_permit(struct rtrs_clt_sess *clt, enum rtrs_clt_con_type con_type) 64 { 65 size_t max_depth = clt->queue_depth; 66 struct rtrs_permit *permit; 67 int bit; 68 69 /* 70 * Adapted from null_blk get_tag(). Callers from different cpus may 71 * grab the same bit, since find_first_zero_bit is not atomic. 72 * But then the test_and_set_bit_lock will fail for all the 73 * callers but one, so that they will loop again. 74 * This way an explicit spinlock is not required. 75 */ 76 do { 77 bit = find_first_zero_bit(clt->permits_map, max_depth); 78 if (bit >= max_depth) 79 return NULL; 80 } while (test_and_set_bit_lock(bit, clt->permits_map)); 81 82 permit = get_permit(clt, bit); 83 WARN_ON(permit->mem_id != bit); 84 permit->cpu_id = raw_smp_processor_id(); 85 permit->con_type = con_type; 86 87 return permit; 88 } 89 90 static inline void __rtrs_put_permit(struct rtrs_clt_sess *clt, 91 struct rtrs_permit *permit) 92 { 93 clear_bit_unlock(permit->mem_id, clt->permits_map); 94 } 95 96 /** 97 * rtrs_clt_get_permit() - allocates permit for future RDMA operation 98 * @clt: Current session 99 * @con_type: Type of connection to use with the permit 100 * @can_wait: Wait type 101 * 102 * Description: 103 * Allocates permit for the following RDMA operation. Permit is used 104 * to preallocate all resources and to propagate memory pressure 105 * up earlier. 106 * 107 * Context: 108 * Can sleep if @wait == RTRS_PERMIT_WAIT 109 */ 110 struct rtrs_permit *rtrs_clt_get_permit(struct rtrs_clt_sess *clt, 111 enum rtrs_clt_con_type con_type, 112 enum wait_type can_wait) 113 { 114 struct rtrs_permit *permit; 115 DEFINE_WAIT(wait); 116 117 permit = __rtrs_get_permit(clt, con_type); 118 if (permit || !can_wait) 119 return permit; 120 121 do { 122 prepare_to_wait(&clt->permits_wait, &wait, 123 TASK_UNINTERRUPTIBLE); 124 permit = __rtrs_get_permit(clt, con_type); 125 if (permit) 126 break; 127 128 io_schedule(); 129 } while (1); 130 131 finish_wait(&clt->permits_wait, &wait); 132 133 return permit; 134 } 135 EXPORT_SYMBOL(rtrs_clt_get_permit); 136 137 /** 138 * rtrs_clt_put_permit() - puts allocated permit 139 * @clt: Current session 140 * @permit: Permit to be freed 141 * 142 * Context: 143 * Does not matter 144 */ 145 void rtrs_clt_put_permit(struct rtrs_clt_sess *clt, 146 struct rtrs_permit *permit) 147 { 148 if (WARN_ON(!test_bit(permit->mem_id, clt->permits_map))) 149 return; 150 151 __rtrs_put_permit(clt, permit); 152 153 /* 154 * rtrs_clt_get_permit() adds itself to the &clt->permits_wait list 155 * before calling schedule(). So if rtrs_clt_get_permit() is sleeping 156 * it must have added itself to &clt->permits_wait before 157 * __rtrs_put_permit() finished. 158 * Hence it is safe to guard wake_up() with a waitqueue_active() test. 159 */ 160 if (waitqueue_active(&clt->permits_wait)) 161 wake_up(&clt->permits_wait); 162 } 163 EXPORT_SYMBOL(rtrs_clt_put_permit); 164 165 /** 166 * rtrs_permit_to_clt_con() - returns RDMA connection pointer by the permit 167 * @clt_path: client path pointer 168 * @permit: permit for the allocation of the RDMA buffer 169 * Note: 170 * IO connection starts from 1. 171 * 0 connection is for user messages. 172 */ 173 static 174 struct rtrs_clt_con *rtrs_permit_to_clt_con(struct rtrs_clt_path *clt_path, 175 struct rtrs_permit *permit) 176 { 177 int id = 0; 178 179 if (permit->con_type == RTRS_IO_CON) 180 id = (permit->cpu_id % (clt_path->s.irq_con_num - 1)) + 1; 181 182 return to_clt_con(clt_path->s.con[id]); 183 } 184 185 /** 186 * rtrs_clt_change_state() - change the session state through session state 187 * machine. 188 * 189 * @clt_path: client path to change the state of. 190 * @new_state: state to change to. 191 * 192 * returns true if sess's state is changed to new state, otherwise return false. 193 * 194 * Locks: 195 * state_wq lock must be hold. 196 */ 197 static bool rtrs_clt_change_state(struct rtrs_clt_path *clt_path, 198 enum rtrs_clt_state new_state) 199 { 200 enum rtrs_clt_state old_state; 201 bool changed = false; 202 203 lockdep_assert_held(&clt_path->state_wq.lock); 204 205 old_state = clt_path->state; 206 switch (new_state) { 207 case RTRS_CLT_CONNECTING: 208 switch (old_state) { 209 case RTRS_CLT_RECONNECTING: 210 changed = true; 211 fallthrough; 212 default: 213 break; 214 } 215 break; 216 case RTRS_CLT_RECONNECTING: 217 switch (old_state) { 218 case RTRS_CLT_CONNECTED: 219 case RTRS_CLT_CONNECTING_ERR: 220 case RTRS_CLT_CLOSED: 221 changed = true; 222 fallthrough; 223 default: 224 break; 225 } 226 break; 227 case RTRS_CLT_CONNECTED: 228 switch (old_state) { 229 case RTRS_CLT_CONNECTING: 230 changed = true; 231 fallthrough; 232 default: 233 break; 234 } 235 break; 236 case RTRS_CLT_CONNECTING_ERR: 237 switch (old_state) { 238 case RTRS_CLT_CONNECTING: 239 changed = true; 240 fallthrough; 241 default: 242 break; 243 } 244 break; 245 case RTRS_CLT_CLOSING: 246 switch (old_state) { 247 case RTRS_CLT_CONNECTING: 248 case RTRS_CLT_CONNECTING_ERR: 249 case RTRS_CLT_RECONNECTING: 250 case RTRS_CLT_CONNECTED: 251 changed = true; 252 fallthrough; 253 default: 254 break; 255 } 256 break; 257 case RTRS_CLT_CLOSED: 258 switch (old_state) { 259 case RTRS_CLT_CLOSING: 260 changed = true; 261 fallthrough; 262 default: 263 break; 264 } 265 break; 266 case RTRS_CLT_DEAD: 267 switch (old_state) { 268 case RTRS_CLT_CLOSED: 269 changed = true; 270 fallthrough; 271 default: 272 break; 273 } 274 break; 275 default: 276 break; 277 } 278 if (changed) { 279 clt_path->state = new_state; 280 wake_up_locked(&clt_path->state_wq); 281 } 282 283 return changed; 284 } 285 286 static bool rtrs_clt_change_state_from_to(struct rtrs_clt_path *clt_path, 287 enum rtrs_clt_state old_state, 288 enum rtrs_clt_state new_state) 289 { 290 bool changed = false; 291 292 spin_lock_irq(&clt_path->state_wq.lock); 293 if (clt_path->state == old_state) 294 changed = rtrs_clt_change_state(clt_path, new_state); 295 spin_unlock_irq(&clt_path->state_wq.lock); 296 297 return changed; 298 } 299 300 static void rtrs_clt_stop_and_destroy_conns(struct rtrs_clt_path *clt_path); 301 static void rtrs_rdma_error_recovery(struct rtrs_clt_con *con) 302 { 303 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 304 305 if (rtrs_clt_change_state_from_to(clt_path, 306 RTRS_CLT_CONNECTED, 307 RTRS_CLT_RECONNECTING)) { 308 queue_work(rtrs_wq, &clt_path->err_recovery_work); 309 } else { 310 /* 311 * Error can happen just on establishing new connection, 312 * so notify waiter with error state, waiter is responsible 313 * for cleaning the rest and reconnect if needed. 314 */ 315 rtrs_clt_change_state_from_to(clt_path, 316 RTRS_CLT_CONNECTING, 317 RTRS_CLT_CONNECTING_ERR); 318 } 319 } 320 321 static void rtrs_clt_fast_reg_done(struct ib_cq *cq, struct ib_wc *wc) 322 { 323 struct rtrs_clt_con *con = to_clt_con(wc->qp->qp_context); 324 325 if (wc->status != IB_WC_SUCCESS) { 326 rtrs_err(con->c.path, "Failed IB_WR_REG_MR: %s\n", 327 ib_wc_status_msg(wc->status)); 328 rtrs_rdma_error_recovery(con); 329 } 330 } 331 332 static struct ib_cqe fast_reg_cqe = { 333 .done = rtrs_clt_fast_reg_done 334 }; 335 336 static void complete_rdma_req(struct rtrs_clt_io_req *req, int errno, 337 bool notify, bool can_wait); 338 339 static void rtrs_clt_inv_rkey_done(struct ib_cq *cq, struct ib_wc *wc) 340 { 341 struct rtrs_clt_io_req *req = 342 container_of(wc->wr_cqe, typeof(*req), inv_cqe); 343 struct rtrs_clt_con *con = to_clt_con(wc->qp->qp_context); 344 345 if (wc->status != IB_WC_SUCCESS) { 346 rtrs_err(con->c.path, "Failed IB_WR_LOCAL_INV: %s\n", 347 ib_wc_status_msg(wc->status)); 348 rtrs_rdma_error_recovery(con); 349 } 350 req->need_inv = false; 351 if (req->need_inv_comp) 352 complete(&req->inv_comp); 353 else 354 /* Complete request from INV callback */ 355 complete_rdma_req(req, req->inv_errno, true, false); 356 } 357 358 static int rtrs_inv_rkey(struct rtrs_clt_io_req *req) 359 { 360 struct rtrs_clt_con *con = req->con; 361 struct ib_send_wr wr = { 362 .opcode = IB_WR_LOCAL_INV, 363 .wr_cqe = &req->inv_cqe, 364 .send_flags = IB_SEND_SIGNALED, 365 .ex.invalidate_rkey = req->mr->rkey, 366 }; 367 req->inv_cqe.done = rtrs_clt_inv_rkey_done; 368 369 return ib_post_send(con->c.qp, &wr, NULL); 370 } 371 372 static void complete_rdma_req(struct rtrs_clt_io_req *req, int errno, 373 bool notify, bool can_wait) 374 { 375 struct rtrs_clt_con *con = req->con; 376 struct rtrs_clt_path *clt_path; 377 int err; 378 379 if (WARN_ON(!req->in_use)) 380 return; 381 if (WARN_ON(!req->con)) 382 return; 383 clt_path = to_clt_path(con->c.path); 384 385 if (req->sg_cnt) { 386 if (req->dir == DMA_FROM_DEVICE && req->need_inv) { 387 /* 388 * We are here to invalidate read requests 389 * ourselves. In normal scenario server should 390 * send INV for all read requests, but 391 * we are here, thus two things could happen: 392 * 393 * 1. this is failover, when errno != 0 394 * and can_wait == 1, 395 * 396 * 2. something totally bad happened and 397 * server forgot to send INV, so we 398 * should do that ourselves. 399 */ 400 401 if (can_wait) { 402 req->need_inv_comp = true; 403 } else { 404 /* This should be IO path, so always notify */ 405 WARN_ON(!notify); 406 /* Save errno for INV callback */ 407 req->inv_errno = errno; 408 } 409 410 refcount_inc(&req->ref); 411 err = rtrs_inv_rkey(req); 412 if (err) { 413 rtrs_err(con->c.path, "Send INV WR key=%#x: %d\n", 414 req->mr->rkey, err); 415 } else if (can_wait) { 416 wait_for_completion(&req->inv_comp); 417 } else { 418 /* 419 * Something went wrong, so request will be 420 * completed from INV callback. 421 */ 422 WARN_ON_ONCE(1); 423 424 return; 425 } 426 if (!refcount_dec_and_test(&req->ref)) 427 return; 428 } 429 ib_dma_unmap_sg(clt_path->s.dev->ib_dev, req->sglist, 430 req->sg_cnt, req->dir); 431 } 432 if (!refcount_dec_and_test(&req->ref)) 433 return; 434 if (req->mp_policy == MP_POLICY_MIN_INFLIGHT) 435 atomic_dec(&clt_path->stats->inflight); 436 437 req->in_use = false; 438 req->con = NULL; 439 440 if (errno) { 441 rtrs_err_rl(con->c.path, "IO request failed: error=%d path=%s [%s:%u] notify=%d\n", 442 errno, kobject_name(&clt_path->kobj), clt_path->hca_name, 443 clt_path->hca_port, notify); 444 } 445 446 if (notify) 447 req->conf(req->priv, errno); 448 } 449 450 static int rtrs_post_send_rdma(struct rtrs_clt_con *con, 451 struct rtrs_clt_io_req *req, 452 struct rtrs_rbuf *rbuf, u32 off, 453 u32 imm, struct ib_send_wr *wr) 454 { 455 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 456 enum ib_send_flags flags; 457 struct ib_sge sge; 458 459 if (!req->sg_size) { 460 rtrs_wrn(con->c.path, 461 "Doing RDMA Write failed, no data supplied\n"); 462 return -EINVAL; 463 } 464 465 /* user data and user message in the first list element */ 466 sge.addr = req->iu->dma_addr; 467 sge.length = req->sg_size; 468 sge.lkey = clt_path->s.dev->ib_pd->local_dma_lkey; 469 470 /* 471 * From time to time we have to post signalled sends, 472 * or send queue will fill up and only QP reset can help. 473 */ 474 flags = atomic_inc_return(&con->c.wr_cnt) % clt_path->s.signal_interval ? 475 0 : IB_SEND_SIGNALED; 476 477 ib_dma_sync_single_for_device(clt_path->s.dev->ib_dev, 478 req->iu->dma_addr, 479 req->sg_size, DMA_TO_DEVICE); 480 481 return rtrs_iu_post_rdma_write_imm(&con->c, req->iu, &sge, 1, 482 rbuf->rkey, rbuf->addr + off, 483 imm, flags, wr, NULL); 484 } 485 486 static void process_io_rsp(struct rtrs_clt_path *clt_path, u32 msg_id, 487 s16 errno, bool w_inval) 488 { 489 struct rtrs_clt_io_req *req; 490 491 if (WARN_ON(msg_id >= clt_path->queue_depth)) 492 return; 493 494 req = &clt_path->reqs[msg_id]; 495 /* Drop need_inv if server responded with send with invalidation */ 496 req->need_inv &= !w_inval; 497 complete_rdma_req(req, errno, true, false); 498 } 499 500 static void rtrs_clt_recv_done(struct rtrs_clt_con *con, struct ib_wc *wc) 501 { 502 struct rtrs_iu *iu; 503 int err; 504 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 505 506 WARN_ON((clt_path->flags & RTRS_MSG_NEW_RKEY_F) == 0); 507 iu = container_of(wc->wr_cqe, struct rtrs_iu, 508 cqe); 509 err = rtrs_iu_post_recv(&con->c, iu); 510 if (err) { 511 rtrs_err(con->c.path, "post iu failed %d\n", err); 512 rtrs_rdma_error_recovery(con); 513 } 514 } 515 516 static void rtrs_clt_rkey_rsp_done(struct rtrs_clt_con *con, struct ib_wc *wc) 517 { 518 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 519 struct rtrs_msg_rkey_rsp *msg; 520 u32 imm_type, imm_payload; 521 bool w_inval = false; 522 struct rtrs_iu *iu; 523 u32 buf_id; 524 int err; 525 526 WARN_ON((clt_path->flags & RTRS_MSG_NEW_RKEY_F) == 0); 527 528 iu = container_of(wc->wr_cqe, struct rtrs_iu, cqe); 529 530 if (wc->byte_len < sizeof(*msg)) { 531 rtrs_err(con->c.path, "rkey response is malformed: size %d\n", 532 wc->byte_len); 533 goto out; 534 } 535 ib_dma_sync_single_for_cpu(clt_path->s.dev->ib_dev, iu->dma_addr, 536 iu->size, DMA_FROM_DEVICE); 537 msg = iu->buf; 538 if (le16_to_cpu(msg->type) != RTRS_MSG_RKEY_RSP) { 539 rtrs_err(clt_path->clt, 540 "rkey response is malformed: type %d\n", 541 le16_to_cpu(msg->type)); 542 goto out; 543 } 544 buf_id = le16_to_cpu(msg->buf_id); 545 if (WARN_ON(buf_id >= clt_path->queue_depth)) 546 goto out; 547 548 rtrs_from_imm(be32_to_cpu(wc->ex.imm_data), &imm_type, &imm_payload); 549 if (imm_type == RTRS_IO_RSP_IMM || 550 imm_type == RTRS_IO_RSP_W_INV_IMM) { 551 u32 msg_id; 552 553 w_inval = (imm_type == RTRS_IO_RSP_W_INV_IMM); 554 rtrs_from_io_rsp_imm(imm_payload, &msg_id, &err); 555 556 if (WARN_ON(buf_id != msg_id)) 557 goto out; 558 clt_path->rbufs[buf_id].rkey = le32_to_cpu(msg->rkey); 559 process_io_rsp(clt_path, msg_id, err, w_inval); 560 } 561 ib_dma_sync_single_for_device(clt_path->s.dev->ib_dev, iu->dma_addr, 562 iu->size, DMA_FROM_DEVICE); 563 return rtrs_clt_recv_done(con, wc); 564 out: 565 rtrs_rdma_error_recovery(con); 566 } 567 568 static void rtrs_clt_rdma_done(struct ib_cq *cq, struct ib_wc *wc); 569 570 static struct ib_cqe io_comp_cqe = { 571 .done = rtrs_clt_rdma_done 572 }; 573 574 /* 575 * Post x2 empty WRs: first is for this RDMA with IMM, 576 * second is for RECV with INV, which happened earlier. 577 */ 578 static int rtrs_post_recv_empty_x2(struct rtrs_con *con, struct ib_cqe *cqe) 579 { 580 struct ib_recv_wr wr_arr[2], *wr; 581 int i; 582 583 memset(wr_arr, 0, sizeof(wr_arr)); 584 for (i = 0; i < ARRAY_SIZE(wr_arr); i++) { 585 wr = &wr_arr[i]; 586 wr->wr_cqe = cqe; 587 if (i) 588 /* Chain backwards */ 589 wr->next = &wr_arr[i - 1]; 590 } 591 592 return ib_post_recv(con->qp, wr, NULL); 593 } 594 595 static void rtrs_clt_rdma_done(struct ib_cq *cq, struct ib_wc *wc) 596 { 597 struct rtrs_clt_con *con = to_clt_con(wc->qp->qp_context); 598 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 599 u32 imm_type, imm_payload; 600 bool w_inval = false; 601 int err; 602 603 if (wc->status != IB_WC_SUCCESS) { 604 if (wc->status != IB_WC_WR_FLUSH_ERR) { 605 rtrs_err(clt_path->clt, "RDMA failed: %s\n", 606 ib_wc_status_msg(wc->status)); 607 rtrs_rdma_error_recovery(con); 608 } 609 return; 610 } 611 rtrs_clt_update_wc_stats(con); 612 613 switch (wc->opcode) { 614 case IB_WC_RECV_RDMA_WITH_IMM: 615 /* 616 * post_recv() RDMA write completions of IO reqs (read/write) 617 * and hb 618 */ 619 if (WARN_ON(wc->wr_cqe->done != rtrs_clt_rdma_done)) 620 return; 621 rtrs_from_imm(be32_to_cpu(wc->ex.imm_data), 622 &imm_type, &imm_payload); 623 if (imm_type == RTRS_IO_RSP_IMM || 624 imm_type == RTRS_IO_RSP_W_INV_IMM) { 625 u32 msg_id; 626 627 w_inval = (imm_type == RTRS_IO_RSP_W_INV_IMM); 628 rtrs_from_io_rsp_imm(imm_payload, &msg_id, &err); 629 630 process_io_rsp(clt_path, msg_id, err, w_inval); 631 } else if (imm_type == RTRS_HB_MSG_IMM) { 632 WARN_ON(con->c.cid); 633 rtrs_send_hb_ack(&clt_path->s); 634 if (clt_path->flags & RTRS_MSG_NEW_RKEY_F) 635 return rtrs_clt_recv_done(con, wc); 636 } else if (imm_type == RTRS_HB_ACK_IMM) { 637 WARN_ON(con->c.cid); 638 clt_path->s.hb_missed_cnt = 0; 639 clt_path->s.hb_cur_latency = 640 ktime_sub(ktime_get(), clt_path->s.hb_last_sent); 641 if (clt_path->flags & RTRS_MSG_NEW_RKEY_F) 642 return rtrs_clt_recv_done(con, wc); 643 } else { 644 rtrs_wrn(con->c.path, "Unknown IMM type %u\n", 645 imm_type); 646 } 647 if (w_inval) 648 /* 649 * Post x2 empty WRs: first is for this RDMA with IMM, 650 * second is for RECV with INV, which happened earlier. 651 */ 652 err = rtrs_post_recv_empty_x2(&con->c, &io_comp_cqe); 653 else 654 err = rtrs_post_recv_empty(&con->c, &io_comp_cqe); 655 if (err) { 656 rtrs_err(con->c.path, "rtrs_post_recv_empty(): %d\n", 657 err); 658 rtrs_rdma_error_recovery(con); 659 } 660 break; 661 case IB_WC_RECV: 662 /* 663 * Key invalidations from server side 664 */ 665 WARN_ON(!(wc->wc_flags & IB_WC_WITH_INVALIDATE || 666 wc->wc_flags & IB_WC_WITH_IMM)); 667 WARN_ON(wc->wr_cqe->done != rtrs_clt_rdma_done); 668 if (clt_path->flags & RTRS_MSG_NEW_RKEY_F) { 669 if (wc->wc_flags & IB_WC_WITH_INVALIDATE) 670 return rtrs_clt_recv_done(con, wc); 671 672 return rtrs_clt_rkey_rsp_done(con, wc); 673 } 674 break; 675 case IB_WC_RDMA_WRITE: 676 /* 677 * post_send() RDMA write completions of IO reqs (read/write) 678 * and hb. 679 */ 680 break; 681 682 default: 683 rtrs_wrn(clt_path->clt, "Unexpected WC type: %d\n", wc->opcode); 684 return; 685 } 686 } 687 688 static int post_recv_io(struct rtrs_clt_con *con, size_t q_size) 689 { 690 int err, i; 691 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 692 693 for (i = 0; i < q_size; i++) { 694 if (clt_path->flags & RTRS_MSG_NEW_RKEY_F) { 695 struct rtrs_iu *iu = &con->rsp_ius[i]; 696 697 err = rtrs_iu_post_recv(&con->c, iu); 698 } else { 699 err = rtrs_post_recv_empty(&con->c, &io_comp_cqe); 700 } 701 if (err) 702 return err; 703 } 704 705 return 0; 706 } 707 708 static int post_recv_path(struct rtrs_clt_path *clt_path) 709 { 710 size_t q_size = 0; 711 int err, cid; 712 713 for (cid = 0; cid < clt_path->s.con_num; cid++) { 714 if (cid == 0) 715 q_size = SERVICE_CON_QUEUE_DEPTH; 716 else 717 q_size = clt_path->queue_depth; 718 719 /* 720 * x2 for RDMA read responses + FR key invalidations, 721 * RDMA writes do not require any FR registrations. 722 */ 723 q_size *= 2; 724 725 err = post_recv_io(to_clt_con(clt_path->s.con[cid]), q_size); 726 if (err) { 727 rtrs_err(clt_path->clt, "post_recv_io(), err: %d\n", 728 err); 729 return err; 730 } 731 } 732 733 return 0; 734 } 735 736 struct path_it { 737 int i; 738 struct list_head skip_list; 739 struct rtrs_clt_sess *clt; 740 struct rtrs_clt_path *(*next_path)(struct path_it *it); 741 }; 742 743 /* 744 * rtrs_clt_get_next_path_or_null - get clt path from the list or return NULL 745 * @head: the head for the list. 746 * @clt_path: The element to take the next clt_path from. 747 * 748 * Next clt path returned in round-robin fashion, i.e. head will be skipped, 749 * but if list is observed as empty, NULL will be returned. 750 * 751 * This function may safely run concurrently with the _rcu list-mutation 752 * primitives such as list_add_rcu() as long as it's guarded by rcu_read_lock(). 753 */ 754 static inline struct rtrs_clt_path * 755 rtrs_clt_get_next_path_or_null(struct list_head *head, struct rtrs_clt_path *clt_path) 756 { 757 return list_next_or_null_rcu(head, &clt_path->s.entry, typeof(*clt_path), s.entry) ?: 758 list_next_or_null_rcu(head, 759 READ_ONCE((&clt_path->s.entry)->next), 760 typeof(*clt_path), s.entry); 761 } 762 763 /** 764 * get_next_path_rr() - Returns path in round-robin fashion. 765 * @it: the path pointer 766 * 767 * Related to @MP_POLICY_RR 768 * 769 * Locks: 770 * rcu_read_lock() must be hold. 771 */ 772 static struct rtrs_clt_path *get_next_path_rr(struct path_it *it) 773 { 774 struct rtrs_clt_path __rcu **ppcpu_path; 775 struct rtrs_clt_path *path; 776 struct rtrs_clt_sess *clt; 777 778 clt = it->clt; 779 780 /* 781 * Here we use two RCU objects: @paths_list and @pcpu_path 782 * pointer. See rtrs_clt_remove_path_from_arr() for details 783 * how that is handled. 784 */ 785 786 ppcpu_path = this_cpu_ptr(clt->pcpu_path); 787 path = rcu_dereference(*ppcpu_path); 788 if (!path) 789 path = list_first_or_null_rcu(&clt->paths_list, 790 typeof(*path), s.entry); 791 else 792 path = rtrs_clt_get_next_path_or_null(&clt->paths_list, path); 793 794 rcu_assign_pointer(*ppcpu_path, path); 795 796 return path; 797 } 798 799 /** 800 * get_next_path_min_inflight() - Returns path with minimal inflight count. 801 * @it: the path pointer 802 * 803 * Related to @MP_POLICY_MIN_INFLIGHT 804 * 805 * Locks: 806 * rcu_read_lock() must be hold. 807 */ 808 static struct rtrs_clt_path *get_next_path_min_inflight(struct path_it *it) 809 { 810 struct rtrs_clt_path *min_path = NULL; 811 struct rtrs_clt_sess *clt = it->clt; 812 struct rtrs_clt_path *clt_path; 813 int min_inflight = INT_MAX; 814 int inflight; 815 816 list_for_each_entry_rcu(clt_path, &clt->paths_list, s.entry) { 817 if (READ_ONCE(clt_path->state) != RTRS_CLT_CONNECTED) 818 continue; 819 820 if (!list_empty(raw_cpu_ptr(clt_path->mp_skip_entry))) 821 continue; 822 823 inflight = atomic_read(&clt_path->stats->inflight); 824 825 if (inflight < min_inflight) { 826 min_inflight = inflight; 827 min_path = clt_path; 828 } 829 } 830 831 /* 832 * add the path to the skip list, so that next time we can get 833 * a different one 834 */ 835 if (min_path) 836 list_add(raw_cpu_ptr(min_path->mp_skip_entry), &it->skip_list); 837 838 return min_path; 839 } 840 841 /** 842 * get_next_path_min_latency() - Returns path with minimal latency. 843 * @it: the path pointer 844 * 845 * Return: a path with the lowest latency or NULL if all paths are tried 846 * 847 * Locks: 848 * rcu_read_lock() must be hold. 849 * 850 * Related to @MP_POLICY_MIN_LATENCY 851 * 852 * This DOES skip an already-tried path. 853 * There is a skip-list to skip a path if the path has tried but failed. 854 * It will try the minimum latency path and then the second minimum latency 855 * path and so on. Finally it will return NULL if all paths are tried. 856 * Therefore the caller MUST check the returned 857 * path is NULL and trigger the IO error. 858 */ 859 static struct rtrs_clt_path *get_next_path_min_latency(struct path_it *it) 860 { 861 struct rtrs_clt_path *min_path = NULL; 862 struct rtrs_clt_sess *clt = it->clt; 863 struct rtrs_clt_path *clt_path; 864 ktime_t min_latency = KTIME_MAX; 865 ktime_t latency; 866 867 list_for_each_entry_rcu(clt_path, &clt->paths_list, s.entry) { 868 if (READ_ONCE(clt_path->state) != RTRS_CLT_CONNECTED) 869 continue; 870 871 if (!list_empty(raw_cpu_ptr(clt_path->mp_skip_entry))) 872 continue; 873 874 latency = clt_path->s.hb_cur_latency; 875 876 if (latency < min_latency) { 877 min_latency = latency; 878 min_path = clt_path; 879 } 880 } 881 882 /* 883 * add the path to the skip list, so that next time we can get 884 * a different one 885 */ 886 if (min_path) 887 list_add(raw_cpu_ptr(min_path->mp_skip_entry), &it->skip_list); 888 889 return min_path; 890 } 891 892 static inline void path_it_init(struct path_it *it, struct rtrs_clt_sess *clt) 893 { 894 INIT_LIST_HEAD(&it->skip_list); 895 it->clt = clt; 896 it->i = 0; 897 898 if (clt->mp_policy == MP_POLICY_RR) 899 it->next_path = get_next_path_rr; 900 else if (clt->mp_policy == MP_POLICY_MIN_INFLIGHT) 901 it->next_path = get_next_path_min_inflight; 902 else 903 it->next_path = get_next_path_min_latency; 904 } 905 906 static inline void path_it_deinit(struct path_it *it) 907 { 908 struct list_head *skip, *tmp; 909 /* 910 * The skip_list is used only for the MIN_INFLIGHT and MIN_LATENCY policies. 911 * We need to remove paths from it, so that next IO can insert 912 * paths (->mp_skip_entry) into a skip_list again. 913 */ 914 list_for_each_safe(skip, tmp, &it->skip_list) 915 list_del_init(skip); 916 } 917 918 /** 919 * rtrs_clt_init_req() - Initialize an rtrs_clt_io_req holding information 920 * about an inflight IO. 921 * The user buffer holding user control message (not data) is copied into 922 * the corresponding buffer of rtrs_iu (req->iu->buf), which later on will 923 * also hold the control message of rtrs. 924 * @req: an io request holding information about IO. 925 * @clt_path: client path 926 * @conf: conformation callback function to notify upper layer. 927 * @permit: permit for allocation of RDMA remote buffer 928 * @priv: private pointer 929 * @vec: kernel vector containing control message 930 * @usr_len: length of the user message 931 * @sg: scater list for IO data 932 * @sg_cnt: number of scater list entries 933 * @data_len: length of the IO data 934 * @dir: direction of the IO. 935 */ 936 static void rtrs_clt_init_req(struct rtrs_clt_io_req *req, 937 struct rtrs_clt_path *clt_path, 938 void (*conf)(void *priv, int errno), 939 struct rtrs_permit *permit, void *priv, 940 const struct kvec *vec, size_t usr_len, 941 struct scatterlist *sg, size_t sg_cnt, 942 size_t data_len, int dir) 943 { 944 struct iov_iter iter; 945 size_t len; 946 947 req->permit = permit; 948 req->in_use = true; 949 req->usr_len = usr_len; 950 req->data_len = data_len; 951 req->sglist = sg; 952 req->sg_cnt = sg_cnt; 953 req->priv = priv; 954 req->dir = dir; 955 req->con = rtrs_permit_to_clt_con(clt_path, permit); 956 req->conf = conf; 957 req->need_inv = false; 958 req->need_inv_comp = false; 959 req->inv_errno = 0; 960 refcount_set(&req->ref, 1); 961 req->mp_policy = clt_path->clt->mp_policy; 962 963 iov_iter_kvec(&iter, READ, vec, 1, usr_len); 964 len = _copy_from_iter(req->iu->buf, usr_len, &iter); 965 WARN_ON(len != usr_len); 966 967 reinit_completion(&req->inv_comp); 968 } 969 970 static struct rtrs_clt_io_req * 971 rtrs_clt_get_req(struct rtrs_clt_path *clt_path, 972 void (*conf)(void *priv, int errno), 973 struct rtrs_permit *permit, void *priv, 974 const struct kvec *vec, size_t usr_len, 975 struct scatterlist *sg, size_t sg_cnt, 976 size_t data_len, int dir) 977 { 978 struct rtrs_clt_io_req *req; 979 980 req = &clt_path->reqs[permit->mem_id]; 981 rtrs_clt_init_req(req, clt_path, conf, permit, priv, vec, usr_len, 982 sg, sg_cnt, data_len, dir); 983 return req; 984 } 985 986 static struct rtrs_clt_io_req * 987 rtrs_clt_get_copy_req(struct rtrs_clt_path *alive_path, 988 struct rtrs_clt_io_req *fail_req) 989 { 990 struct rtrs_clt_io_req *req; 991 struct kvec vec = { 992 .iov_base = fail_req->iu->buf, 993 .iov_len = fail_req->usr_len 994 }; 995 996 req = &alive_path->reqs[fail_req->permit->mem_id]; 997 rtrs_clt_init_req(req, alive_path, fail_req->conf, fail_req->permit, 998 fail_req->priv, &vec, fail_req->usr_len, 999 fail_req->sglist, fail_req->sg_cnt, 1000 fail_req->data_len, fail_req->dir); 1001 return req; 1002 } 1003 1004 static int rtrs_post_rdma_write_sg(struct rtrs_clt_con *con, 1005 struct rtrs_clt_io_req *req, 1006 struct rtrs_rbuf *rbuf, bool fr_en, 1007 u32 count, u32 size, u32 imm, 1008 struct ib_send_wr *wr, 1009 struct ib_send_wr *tail) 1010 { 1011 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 1012 struct ib_sge *sge = req->sge; 1013 enum ib_send_flags flags; 1014 struct scatterlist *sg; 1015 size_t num_sge; 1016 int i; 1017 struct ib_send_wr *ptail = NULL; 1018 1019 if (fr_en) { 1020 i = 0; 1021 sge[i].addr = req->mr->iova; 1022 sge[i].length = req->mr->length; 1023 sge[i].lkey = req->mr->lkey; 1024 i++; 1025 num_sge = 2; 1026 ptail = tail; 1027 } else { 1028 for_each_sg(req->sglist, sg, count, i) { 1029 sge[i].addr = sg_dma_address(sg); 1030 sge[i].length = sg_dma_len(sg); 1031 sge[i].lkey = clt_path->s.dev->ib_pd->local_dma_lkey; 1032 } 1033 num_sge = 1 + count; 1034 } 1035 sge[i].addr = req->iu->dma_addr; 1036 sge[i].length = size; 1037 sge[i].lkey = clt_path->s.dev->ib_pd->local_dma_lkey; 1038 1039 /* 1040 * From time to time we have to post signalled sends, 1041 * or send queue will fill up and only QP reset can help. 1042 */ 1043 flags = atomic_inc_return(&con->c.wr_cnt) % clt_path->s.signal_interval ? 1044 0 : IB_SEND_SIGNALED; 1045 1046 ib_dma_sync_single_for_device(clt_path->s.dev->ib_dev, 1047 req->iu->dma_addr, 1048 size, DMA_TO_DEVICE); 1049 1050 return rtrs_iu_post_rdma_write_imm(&con->c, req->iu, sge, num_sge, 1051 rbuf->rkey, rbuf->addr, imm, 1052 flags, wr, ptail); 1053 } 1054 1055 static int rtrs_map_sg_fr(struct rtrs_clt_io_req *req, size_t count) 1056 { 1057 int nr; 1058 1059 /* Align the MR to a 4K page size to match the block virt boundary */ 1060 nr = ib_map_mr_sg(req->mr, req->sglist, count, NULL, SZ_4K); 1061 if (nr < 0) 1062 return nr; 1063 if (nr < req->sg_cnt) 1064 return -EINVAL; 1065 ib_update_fast_reg_key(req->mr, ib_inc_rkey(req->mr->rkey)); 1066 1067 return nr; 1068 } 1069 1070 static int rtrs_clt_write_req(struct rtrs_clt_io_req *req) 1071 { 1072 struct rtrs_clt_con *con = req->con; 1073 struct rtrs_path *s = con->c.path; 1074 struct rtrs_clt_path *clt_path = to_clt_path(s); 1075 struct rtrs_msg_rdma_write *msg; 1076 1077 struct rtrs_rbuf *rbuf; 1078 int ret, count = 0; 1079 u32 imm, buf_id; 1080 struct ib_reg_wr rwr; 1081 struct ib_send_wr inv_wr; 1082 struct ib_send_wr *wr = NULL; 1083 bool fr_en = false; 1084 1085 const size_t tsize = sizeof(*msg) + req->data_len + req->usr_len; 1086 1087 if (tsize > clt_path->chunk_size) { 1088 rtrs_wrn(s, "Write request failed, size too big %zu > %d\n", 1089 tsize, clt_path->chunk_size); 1090 return -EMSGSIZE; 1091 } 1092 if (req->sg_cnt) { 1093 count = ib_dma_map_sg(clt_path->s.dev->ib_dev, req->sglist, 1094 req->sg_cnt, req->dir); 1095 if (!count) { 1096 rtrs_wrn(s, "Write request failed, map failed\n"); 1097 return -EINVAL; 1098 } 1099 } 1100 /* put rtrs msg after sg and user message */ 1101 msg = req->iu->buf + req->usr_len; 1102 msg->type = cpu_to_le16(RTRS_MSG_WRITE); 1103 msg->usr_len = cpu_to_le16(req->usr_len); 1104 1105 /* rtrs message on server side will be after user data and message */ 1106 imm = req->permit->mem_off + req->data_len + req->usr_len; 1107 imm = rtrs_to_io_req_imm(imm); 1108 buf_id = req->permit->mem_id; 1109 req->sg_size = tsize; 1110 rbuf = &clt_path->rbufs[buf_id]; 1111 1112 if (count) { 1113 ret = rtrs_map_sg_fr(req, count); 1114 if (ret < 0) { 1115 rtrs_err_rl(s, 1116 "Write request failed, failed to map fast reg. data, err: %d\n", 1117 ret); 1118 ib_dma_unmap_sg(clt_path->s.dev->ib_dev, req->sglist, 1119 req->sg_cnt, req->dir); 1120 return ret; 1121 } 1122 inv_wr = (struct ib_send_wr) { 1123 .opcode = IB_WR_LOCAL_INV, 1124 .wr_cqe = &req->inv_cqe, 1125 .send_flags = IB_SEND_SIGNALED, 1126 .ex.invalidate_rkey = req->mr->rkey, 1127 }; 1128 req->inv_cqe.done = rtrs_clt_inv_rkey_done; 1129 rwr = (struct ib_reg_wr) { 1130 .wr.opcode = IB_WR_REG_MR, 1131 .wr.wr_cqe = &fast_reg_cqe, 1132 .mr = req->mr, 1133 .key = req->mr->rkey, 1134 .access = (IB_ACCESS_LOCAL_WRITE), 1135 }; 1136 wr = &rwr.wr; 1137 fr_en = true; 1138 refcount_inc(&req->ref); 1139 } 1140 /* 1141 * Update stats now, after request is successfully sent it is not 1142 * safe anymore to touch it. 1143 */ 1144 rtrs_clt_update_all_stats(req, WRITE); 1145 1146 ret = rtrs_post_rdma_write_sg(req->con, req, rbuf, fr_en, count, 1147 req->usr_len + sizeof(*msg), 1148 imm, wr, &inv_wr); 1149 if (ret) { 1150 rtrs_err_rl(s, 1151 "Write request failed: error=%d path=%s [%s:%u]\n", 1152 ret, kobject_name(&clt_path->kobj), clt_path->hca_name, 1153 clt_path->hca_port); 1154 if (req->mp_policy == MP_POLICY_MIN_INFLIGHT) 1155 atomic_dec(&clt_path->stats->inflight); 1156 if (req->sg_cnt) 1157 ib_dma_unmap_sg(clt_path->s.dev->ib_dev, req->sglist, 1158 req->sg_cnt, req->dir); 1159 } 1160 1161 return ret; 1162 } 1163 1164 static int rtrs_clt_read_req(struct rtrs_clt_io_req *req) 1165 { 1166 struct rtrs_clt_con *con = req->con; 1167 struct rtrs_path *s = con->c.path; 1168 struct rtrs_clt_path *clt_path = to_clt_path(s); 1169 struct rtrs_msg_rdma_read *msg; 1170 struct rtrs_ib_dev *dev = clt_path->s.dev; 1171 1172 struct ib_reg_wr rwr; 1173 struct ib_send_wr *wr = NULL; 1174 1175 int ret, count = 0; 1176 u32 imm, buf_id; 1177 1178 const size_t tsize = sizeof(*msg) + req->data_len + req->usr_len; 1179 1180 if (tsize > clt_path->chunk_size) { 1181 rtrs_wrn(s, 1182 "Read request failed, message size is %zu, bigger than CHUNK_SIZE %d\n", 1183 tsize, clt_path->chunk_size); 1184 return -EMSGSIZE; 1185 } 1186 1187 if (req->sg_cnt) { 1188 count = ib_dma_map_sg(dev->ib_dev, req->sglist, req->sg_cnt, 1189 req->dir); 1190 if (!count) { 1191 rtrs_wrn(s, 1192 "Read request failed, dma map failed\n"); 1193 return -EINVAL; 1194 } 1195 } 1196 /* put our message into req->buf after user message*/ 1197 msg = req->iu->buf + req->usr_len; 1198 msg->type = cpu_to_le16(RTRS_MSG_READ); 1199 msg->usr_len = cpu_to_le16(req->usr_len); 1200 1201 if (count) { 1202 ret = rtrs_map_sg_fr(req, count); 1203 if (ret < 0) { 1204 rtrs_err_rl(s, 1205 "Read request failed, failed to map fast reg. data, err: %d\n", 1206 ret); 1207 ib_dma_unmap_sg(dev->ib_dev, req->sglist, req->sg_cnt, 1208 req->dir); 1209 return ret; 1210 } 1211 rwr = (struct ib_reg_wr) { 1212 .wr.opcode = IB_WR_REG_MR, 1213 .wr.wr_cqe = &fast_reg_cqe, 1214 .mr = req->mr, 1215 .key = req->mr->rkey, 1216 .access = (IB_ACCESS_LOCAL_WRITE | 1217 IB_ACCESS_REMOTE_WRITE), 1218 }; 1219 wr = &rwr.wr; 1220 1221 msg->sg_cnt = cpu_to_le16(1); 1222 msg->flags = cpu_to_le16(RTRS_MSG_NEED_INVAL_F); 1223 1224 msg->desc[0].addr = cpu_to_le64(req->mr->iova); 1225 msg->desc[0].key = cpu_to_le32(req->mr->rkey); 1226 msg->desc[0].len = cpu_to_le32(req->mr->length); 1227 1228 /* Further invalidation is required */ 1229 req->need_inv = !!RTRS_MSG_NEED_INVAL_F; 1230 1231 } else { 1232 msg->sg_cnt = 0; 1233 msg->flags = 0; 1234 } 1235 /* 1236 * rtrs message will be after the space reserved for disk data and 1237 * user message 1238 */ 1239 imm = req->permit->mem_off + req->data_len + req->usr_len; 1240 imm = rtrs_to_io_req_imm(imm); 1241 buf_id = req->permit->mem_id; 1242 1243 req->sg_size = sizeof(*msg); 1244 req->sg_size += le16_to_cpu(msg->sg_cnt) * sizeof(struct rtrs_sg_desc); 1245 req->sg_size += req->usr_len; 1246 1247 /* 1248 * Update stats now, after request is successfully sent it is not 1249 * safe anymore to touch it. 1250 */ 1251 rtrs_clt_update_all_stats(req, READ); 1252 1253 ret = rtrs_post_send_rdma(req->con, req, &clt_path->rbufs[buf_id], 1254 req->data_len, imm, wr); 1255 if (ret) { 1256 rtrs_err_rl(s, 1257 "Read request failed: error=%d path=%s [%s:%u]\n", 1258 ret, kobject_name(&clt_path->kobj), clt_path->hca_name, 1259 clt_path->hca_port); 1260 if (req->mp_policy == MP_POLICY_MIN_INFLIGHT) 1261 atomic_dec(&clt_path->stats->inflight); 1262 req->need_inv = false; 1263 if (req->sg_cnt) 1264 ib_dma_unmap_sg(dev->ib_dev, req->sglist, 1265 req->sg_cnt, req->dir); 1266 } 1267 1268 return ret; 1269 } 1270 1271 /** 1272 * rtrs_clt_failover_req() - Try to find an active path for a failed request 1273 * @clt: clt context 1274 * @fail_req: a failed io request. 1275 */ 1276 static int rtrs_clt_failover_req(struct rtrs_clt_sess *clt, 1277 struct rtrs_clt_io_req *fail_req) 1278 { 1279 struct rtrs_clt_path *alive_path; 1280 struct rtrs_clt_io_req *req; 1281 int err = -ECONNABORTED; 1282 struct path_it it; 1283 1284 rcu_read_lock(); 1285 for (path_it_init(&it, clt); 1286 (alive_path = it.next_path(&it)) && it.i < it.clt->paths_num; 1287 it.i++) { 1288 if (READ_ONCE(alive_path->state) != RTRS_CLT_CONNECTED) 1289 continue; 1290 req = rtrs_clt_get_copy_req(alive_path, fail_req); 1291 if (req->dir == DMA_TO_DEVICE) 1292 err = rtrs_clt_write_req(req); 1293 else 1294 err = rtrs_clt_read_req(req); 1295 if (err) { 1296 req->in_use = false; 1297 continue; 1298 } 1299 /* Success path */ 1300 rtrs_clt_inc_failover_cnt(alive_path->stats); 1301 break; 1302 } 1303 path_it_deinit(&it); 1304 rcu_read_unlock(); 1305 1306 return err; 1307 } 1308 1309 static void fail_all_outstanding_reqs(struct rtrs_clt_path *clt_path) 1310 { 1311 struct rtrs_clt_sess *clt = clt_path->clt; 1312 struct rtrs_clt_io_req *req; 1313 int i, err; 1314 1315 if (!clt_path->reqs) 1316 return; 1317 for (i = 0; i < clt_path->queue_depth; ++i) { 1318 req = &clt_path->reqs[i]; 1319 if (!req->in_use) 1320 continue; 1321 1322 /* 1323 * Safely (without notification) complete failed request. 1324 * After completion this request is still useble and can 1325 * be failovered to another path. 1326 */ 1327 complete_rdma_req(req, -ECONNABORTED, false, true); 1328 1329 err = rtrs_clt_failover_req(clt, req); 1330 if (err) 1331 /* Failover failed, notify anyway */ 1332 req->conf(req->priv, err); 1333 } 1334 } 1335 1336 static void free_path_reqs(struct rtrs_clt_path *clt_path) 1337 { 1338 struct rtrs_clt_io_req *req; 1339 int i; 1340 1341 if (!clt_path->reqs) 1342 return; 1343 for (i = 0; i < clt_path->queue_depth; ++i) { 1344 req = &clt_path->reqs[i]; 1345 if (req->mr) 1346 ib_dereg_mr(req->mr); 1347 kfree(req->sge); 1348 rtrs_iu_free(req->iu, clt_path->s.dev->ib_dev, 1); 1349 } 1350 kfree(clt_path->reqs); 1351 clt_path->reqs = NULL; 1352 } 1353 1354 static int alloc_path_reqs(struct rtrs_clt_path *clt_path) 1355 { 1356 struct rtrs_clt_io_req *req; 1357 int i, err = -ENOMEM; 1358 1359 clt_path->reqs = kcalloc(clt_path->queue_depth, 1360 sizeof(*clt_path->reqs), 1361 GFP_KERNEL); 1362 if (!clt_path->reqs) 1363 return -ENOMEM; 1364 1365 for (i = 0; i < clt_path->queue_depth; ++i) { 1366 req = &clt_path->reqs[i]; 1367 req->iu = rtrs_iu_alloc(1, clt_path->max_hdr_size, GFP_KERNEL, 1368 clt_path->s.dev->ib_dev, 1369 DMA_TO_DEVICE, 1370 rtrs_clt_rdma_done); 1371 if (!req->iu) 1372 goto out; 1373 1374 req->sge = kcalloc(2, sizeof(*req->sge), GFP_KERNEL); 1375 if (!req->sge) 1376 goto out; 1377 1378 req->mr = ib_alloc_mr(clt_path->s.dev->ib_pd, 1379 IB_MR_TYPE_MEM_REG, 1380 clt_path->max_pages_per_mr); 1381 if (IS_ERR(req->mr)) { 1382 err = PTR_ERR(req->mr); 1383 req->mr = NULL; 1384 pr_err("Failed to alloc clt_path->max_pages_per_mr %d\n", 1385 clt_path->max_pages_per_mr); 1386 goto out; 1387 } 1388 1389 init_completion(&req->inv_comp); 1390 } 1391 1392 return 0; 1393 1394 out: 1395 free_path_reqs(clt_path); 1396 1397 return err; 1398 } 1399 1400 static int alloc_permits(struct rtrs_clt_sess *clt) 1401 { 1402 unsigned int chunk_bits; 1403 int err, i; 1404 1405 clt->permits_map = bitmap_zalloc(clt->queue_depth, GFP_KERNEL); 1406 if (!clt->permits_map) { 1407 err = -ENOMEM; 1408 goto out_err; 1409 } 1410 clt->permits = kcalloc(clt->queue_depth, permit_size(clt), GFP_KERNEL); 1411 if (!clt->permits) { 1412 err = -ENOMEM; 1413 goto err_map; 1414 } 1415 chunk_bits = ilog2(clt->queue_depth - 1) + 1; 1416 for (i = 0; i < clt->queue_depth; i++) { 1417 struct rtrs_permit *permit; 1418 1419 permit = get_permit(clt, i); 1420 permit->mem_id = i; 1421 permit->mem_off = i << (MAX_IMM_PAYL_BITS - chunk_bits); 1422 } 1423 1424 return 0; 1425 1426 err_map: 1427 bitmap_free(clt->permits_map); 1428 clt->permits_map = NULL; 1429 out_err: 1430 return err; 1431 } 1432 1433 static void free_permits(struct rtrs_clt_sess *clt) 1434 { 1435 if (clt->permits_map) 1436 wait_event(clt->permits_wait, 1437 bitmap_empty(clt->permits_map, clt->queue_depth)); 1438 1439 bitmap_free(clt->permits_map); 1440 clt->permits_map = NULL; 1441 kfree(clt->permits); 1442 clt->permits = NULL; 1443 } 1444 1445 static void query_fast_reg_mode(struct rtrs_clt_path *clt_path) 1446 { 1447 struct ib_device *ib_dev; 1448 u64 max_pages_per_mr; 1449 int mr_page_shift; 1450 1451 ib_dev = clt_path->s.dev->ib_dev; 1452 1453 /* 1454 * Use the smallest page size supported by the HCA, down to a 1455 * minimum of 4096 bytes. We're unlikely to build large sglists 1456 * out of smaller entries. 1457 */ 1458 mr_page_shift = max(12, ffs(ib_dev->attrs.page_size_cap) - 1); 1459 max_pages_per_mr = ib_dev->attrs.max_mr_size; 1460 do_div(max_pages_per_mr, (1ull << mr_page_shift)); 1461 clt_path->max_pages_per_mr = 1462 min3(clt_path->max_pages_per_mr, (u32)max_pages_per_mr, 1463 ib_dev->attrs.max_fast_reg_page_list_len); 1464 clt_path->clt->max_segments = 1465 min(clt_path->max_pages_per_mr, clt_path->clt->max_segments); 1466 } 1467 1468 static bool rtrs_clt_change_state_get_old(struct rtrs_clt_path *clt_path, 1469 enum rtrs_clt_state new_state, 1470 enum rtrs_clt_state *old_state) 1471 { 1472 bool changed; 1473 1474 spin_lock_irq(&clt_path->state_wq.lock); 1475 if (old_state) 1476 *old_state = clt_path->state; 1477 changed = rtrs_clt_change_state(clt_path, new_state); 1478 spin_unlock_irq(&clt_path->state_wq.lock); 1479 1480 return changed; 1481 } 1482 1483 static void rtrs_clt_hb_err_handler(struct rtrs_con *c) 1484 { 1485 struct rtrs_clt_con *con = container_of(c, typeof(*con), c); 1486 1487 rtrs_rdma_error_recovery(con); 1488 } 1489 1490 static void rtrs_clt_init_hb(struct rtrs_clt_path *clt_path) 1491 { 1492 rtrs_init_hb(&clt_path->s, &io_comp_cqe, 1493 RTRS_HB_INTERVAL_MS, 1494 RTRS_HB_MISSED_MAX, 1495 rtrs_clt_hb_err_handler, 1496 rtrs_wq); 1497 } 1498 1499 static void rtrs_clt_reconnect_work(struct work_struct *work); 1500 static void rtrs_clt_close_work(struct work_struct *work); 1501 1502 static void rtrs_clt_err_recovery_work(struct work_struct *work) 1503 { 1504 struct rtrs_clt_path *clt_path; 1505 struct rtrs_clt_sess *clt; 1506 int delay_ms; 1507 1508 clt_path = container_of(work, struct rtrs_clt_path, err_recovery_work); 1509 clt = clt_path->clt; 1510 delay_ms = clt->reconnect_delay_sec * 1000; 1511 rtrs_clt_stop_and_destroy_conns(clt_path); 1512 queue_delayed_work(rtrs_wq, &clt_path->reconnect_dwork, 1513 msecs_to_jiffies(delay_ms + 1514 prandom_u32() % 1515 RTRS_RECONNECT_SEED)); 1516 } 1517 1518 static struct rtrs_clt_path *alloc_path(struct rtrs_clt_sess *clt, 1519 const struct rtrs_addr *path, 1520 size_t con_num, u32 nr_poll_queues) 1521 { 1522 struct rtrs_clt_path *clt_path; 1523 int err = -ENOMEM; 1524 int cpu; 1525 size_t total_con; 1526 1527 clt_path = kzalloc(sizeof(*clt_path), GFP_KERNEL); 1528 if (!clt_path) 1529 goto err; 1530 1531 /* 1532 * irqmode and poll 1533 * +1: Extra connection for user messages 1534 */ 1535 total_con = con_num + nr_poll_queues + 1; 1536 clt_path->s.con = kcalloc(total_con, sizeof(*clt_path->s.con), 1537 GFP_KERNEL); 1538 if (!clt_path->s.con) 1539 goto err_free_path; 1540 1541 clt_path->s.con_num = total_con; 1542 clt_path->s.irq_con_num = con_num + 1; 1543 1544 clt_path->stats = kzalloc(sizeof(*clt_path->stats), GFP_KERNEL); 1545 if (!clt_path->stats) 1546 goto err_free_con; 1547 1548 mutex_init(&clt_path->init_mutex); 1549 uuid_gen(&clt_path->s.uuid); 1550 memcpy(&clt_path->s.dst_addr, path->dst, 1551 rdma_addr_size((struct sockaddr *)path->dst)); 1552 1553 /* 1554 * rdma_resolve_addr() passes src_addr to cma_bind_addr, which 1555 * checks the sa_family to be non-zero. If user passed src_addr=NULL 1556 * the sess->src_addr will contain only zeros, which is then fine. 1557 */ 1558 if (path->src) 1559 memcpy(&clt_path->s.src_addr, path->src, 1560 rdma_addr_size((struct sockaddr *)path->src)); 1561 strscpy(clt_path->s.sessname, clt->sessname, 1562 sizeof(clt_path->s.sessname)); 1563 clt_path->clt = clt; 1564 clt_path->max_pages_per_mr = RTRS_MAX_SEGMENTS; 1565 init_waitqueue_head(&clt_path->state_wq); 1566 clt_path->state = RTRS_CLT_CONNECTING; 1567 atomic_set(&clt_path->connected_cnt, 0); 1568 INIT_WORK(&clt_path->close_work, rtrs_clt_close_work); 1569 INIT_WORK(&clt_path->err_recovery_work, rtrs_clt_err_recovery_work); 1570 INIT_DELAYED_WORK(&clt_path->reconnect_dwork, rtrs_clt_reconnect_work); 1571 rtrs_clt_init_hb(clt_path); 1572 1573 clt_path->mp_skip_entry = alloc_percpu(typeof(*clt_path->mp_skip_entry)); 1574 if (!clt_path->mp_skip_entry) 1575 goto err_free_stats; 1576 1577 for_each_possible_cpu(cpu) 1578 INIT_LIST_HEAD(per_cpu_ptr(clt_path->mp_skip_entry, cpu)); 1579 1580 err = rtrs_clt_init_stats(clt_path->stats); 1581 if (err) 1582 goto err_free_percpu; 1583 1584 return clt_path; 1585 1586 err_free_percpu: 1587 free_percpu(clt_path->mp_skip_entry); 1588 err_free_stats: 1589 kfree(clt_path->stats); 1590 err_free_con: 1591 kfree(clt_path->s.con); 1592 err_free_path: 1593 kfree(clt_path); 1594 err: 1595 return ERR_PTR(err); 1596 } 1597 1598 void free_path(struct rtrs_clt_path *clt_path) 1599 { 1600 free_percpu(clt_path->mp_skip_entry); 1601 mutex_destroy(&clt_path->init_mutex); 1602 kfree(clt_path->s.con); 1603 kfree(clt_path->rbufs); 1604 kfree(clt_path); 1605 } 1606 1607 static int create_con(struct rtrs_clt_path *clt_path, unsigned int cid) 1608 { 1609 struct rtrs_clt_con *con; 1610 1611 con = kzalloc(sizeof(*con), GFP_KERNEL); 1612 if (!con) 1613 return -ENOMEM; 1614 1615 /* Map first two connections to the first CPU */ 1616 con->cpu = (cid ? cid - 1 : 0) % nr_cpu_ids; 1617 con->c.cid = cid; 1618 con->c.path = &clt_path->s; 1619 /* Align with srv, init as 1 */ 1620 atomic_set(&con->c.wr_cnt, 1); 1621 mutex_init(&con->con_mutex); 1622 1623 clt_path->s.con[cid] = &con->c; 1624 1625 return 0; 1626 } 1627 1628 static void destroy_con(struct rtrs_clt_con *con) 1629 { 1630 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 1631 1632 clt_path->s.con[con->c.cid] = NULL; 1633 mutex_destroy(&con->con_mutex); 1634 kfree(con); 1635 } 1636 1637 static int create_con_cq_qp(struct rtrs_clt_con *con) 1638 { 1639 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 1640 u32 max_send_wr, max_recv_wr, cq_num, max_send_sge, wr_limit; 1641 int err, cq_vector; 1642 struct rtrs_msg_rkey_rsp *rsp; 1643 1644 lockdep_assert_held(&con->con_mutex); 1645 if (con->c.cid == 0) { 1646 max_send_sge = 1; 1647 /* We must be the first here */ 1648 if (WARN_ON(clt_path->s.dev)) 1649 return -EINVAL; 1650 1651 /* 1652 * The whole session uses device from user connection. 1653 * Be careful not to close user connection before ib dev 1654 * is gracefully put. 1655 */ 1656 clt_path->s.dev = rtrs_ib_dev_find_or_add(con->c.cm_id->device, 1657 &dev_pd); 1658 if (!clt_path->s.dev) { 1659 rtrs_wrn(clt_path->clt, 1660 "rtrs_ib_dev_find_get_or_add(): no memory\n"); 1661 return -ENOMEM; 1662 } 1663 clt_path->s.dev_ref = 1; 1664 query_fast_reg_mode(clt_path); 1665 wr_limit = clt_path->s.dev->ib_dev->attrs.max_qp_wr; 1666 /* 1667 * Two (request + registration) completion for send 1668 * Two for recv if always_invalidate is set on server 1669 * or one for recv. 1670 * + 2 for drain and heartbeat 1671 * in case qp gets into error state. 1672 */ 1673 max_send_wr = 1674 min_t(int, wr_limit, SERVICE_CON_QUEUE_DEPTH * 2 + 2); 1675 max_recv_wr = max_send_wr; 1676 } else { 1677 /* 1678 * Here we assume that session members are correctly set. 1679 * This is always true if user connection (cid == 0) is 1680 * established first. 1681 */ 1682 if (WARN_ON(!clt_path->s.dev)) 1683 return -EINVAL; 1684 if (WARN_ON(!clt_path->queue_depth)) 1685 return -EINVAL; 1686 1687 wr_limit = clt_path->s.dev->ib_dev->attrs.max_qp_wr; 1688 /* Shared between connections */ 1689 clt_path->s.dev_ref++; 1690 max_send_wr = min_t(int, wr_limit, 1691 /* QD * (REQ + RSP + FR REGS or INVS) + drain */ 1692 clt_path->queue_depth * 3 + 1); 1693 max_recv_wr = min_t(int, wr_limit, 1694 clt_path->queue_depth * 3 + 1); 1695 max_send_sge = 2; 1696 } 1697 atomic_set(&con->c.sq_wr_avail, max_send_wr); 1698 cq_num = max_send_wr + max_recv_wr; 1699 /* alloc iu to recv new rkey reply when server reports flags set */ 1700 if (clt_path->flags & RTRS_MSG_NEW_RKEY_F || con->c.cid == 0) { 1701 con->rsp_ius = rtrs_iu_alloc(cq_num, sizeof(*rsp), 1702 GFP_KERNEL, 1703 clt_path->s.dev->ib_dev, 1704 DMA_FROM_DEVICE, 1705 rtrs_clt_rdma_done); 1706 if (!con->rsp_ius) 1707 return -ENOMEM; 1708 con->queue_num = cq_num; 1709 } 1710 cq_num = max_send_wr + max_recv_wr; 1711 cq_vector = con->cpu % clt_path->s.dev->ib_dev->num_comp_vectors; 1712 if (con->c.cid >= clt_path->s.irq_con_num) 1713 err = rtrs_cq_qp_create(&clt_path->s, &con->c, max_send_sge, 1714 cq_vector, cq_num, max_send_wr, 1715 max_recv_wr, IB_POLL_DIRECT); 1716 else 1717 err = rtrs_cq_qp_create(&clt_path->s, &con->c, max_send_sge, 1718 cq_vector, cq_num, max_send_wr, 1719 max_recv_wr, IB_POLL_SOFTIRQ); 1720 /* 1721 * In case of error we do not bother to clean previous allocations, 1722 * since destroy_con_cq_qp() must be called. 1723 */ 1724 return err; 1725 } 1726 1727 static void destroy_con_cq_qp(struct rtrs_clt_con *con) 1728 { 1729 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 1730 1731 /* 1732 * Be careful here: destroy_con_cq_qp() can be called even 1733 * create_con_cq_qp() failed, see comments there. 1734 */ 1735 lockdep_assert_held(&con->con_mutex); 1736 rtrs_cq_qp_destroy(&con->c); 1737 if (con->rsp_ius) { 1738 rtrs_iu_free(con->rsp_ius, clt_path->s.dev->ib_dev, 1739 con->queue_num); 1740 con->rsp_ius = NULL; 1741 con->queue_num = 0; 1742 } 1743 if (clt_path->s.dev_ref && !--clt_path->s.dev_ref) { 1744 rtrs_ib_dev_put(clt_path->s.dev); 1745 clt_path->s.dev = NULL; 1746 } 1747 } 1748 1749 static void stop_cm(struct rtrs_clt_con *con) 1750 { 1751 rdma_disconnect(con->c.cm_id); 1752 if (con->c.qp) 1753 ib_drain_qp(con->c.qp); 1754 } 1755 1756 static void destroy_cm(struct rtrs_clt_con *con) 1757 { 1758 rdma_destroy_id(con->c.cm_id); 1759 con->c.cm_id = NULL; 1760 } 1761 1762 static int rtrs_rdma_addr_resolved(struct rtrs_clt_con *con) 1763 { 1764 struct rtrs_path *s = con->c.path; 1765 int err; 1766 1767 mutex_lock(&con->con_mutex); 1768 err = create_con_cq_qp(con); 1769 mutex_unlock(&con->con_mutex); 1770 if (err) { 1771 rtrs_err(s, "create_con_cq_qp(), err: %d\n", err); 1772 return err; 1773 } 1774 err = rdma_resolve_route(con->c.cm_id, RTRS_CONNECT_TIMEOUT_MS); 1775 if (err) 1776 rtrs_err(s, "Resolving route failed, err: %d\n", err); 1777 1778 return err; 1779 } 1780 1781 static int rtrs_rdma_route_resolved(struct rtrs_clt_con *con) 1782 { 1783 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 1784 struct rtrs_clt_sess *clt = clt_path->clt; 1785 struct rtrs_msg_conn_req msg; 1786 struct rdma_conn_param param; 1787 1788 int err; 1789 1790 param = (struct rdma_conn_param) { 1791 .retry_count = 7, 1792 .rnr_retry_count = 7, 1793 .private_data = &msg, 1794 .private_data_len = sizeof(msg), 1795 }; 1796 1797 msg = (struct rtrs_msg_conn_req) { 1798 .magic = cpu_to_le16(RTRS_MAGIC), 1799 .version = cpu_to_le16(RTRS_PROTO_VER), 1800 .cid = cpu_to_le16(con->c.cid), 1801 .cid_num = cpu_to_le16(clt_path->s.con_num), 1802 .recon_cnt = cpu_to_le16(clt_path->s.recon_cnt), 1803 }; 1804 msg.first_conn = clt_path->for_new_clt ? FIRST_CONN : 0; 1805 uuid_copy(&msg.sess_uuid, &clt_path->s.uuid); 1806 uuid_copy(&msg.paths_uuid, &clt->paths_uuid); 1807 1808 err = rdma_connect_locked(con->c.cm_id, ¶m); 1809 if (err) 1810 rtrs_err(clt, "rdma_connect_locked(): %d\n", err); 1811 1812 return err; 1813 } 1814 1815 static int rtrs_rdma_conn_established(struct rtrs_clt_con *con, 1816 struct rdma_cm_event *ev) 1817 { 1818 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 1819 struct rtrs_clt_sess *clt = clt_path->clt; 1820 const struct rtrs_msg_conn_rsp *msg; 1821 u16 version, queue_depth; 1822 int errno; 1823 u8 len; 1824 1825 msg = ev->param.conn.private_data; 1826 len = ev->param.conn.private_data_len; 1827 if (len < sizeof(*msg)) { 1828 rtrs_err(clt, "Invalid RTRS connection response\n"); 1829 return -ECONNRESET; 1830 } 1831 if (le16_to_cpu(msg->magic) != RTRS_MAGIC) { 1832 rtrs_err(clt, "Invalid RTRS magic\n"); 1833 return -ECONNRESET; 1834 } 1835 version = le16_to_cpu(msg->version); 1836 if (version >> 8 != RTRS_PROTO_VER_MAJOR) { 1837 rtrs_err(clt, "Unsupported major RTRS version: %d, expected %d\n", 1838 version >> 8, RTRS_PROTO_VER_MAJOR); 1839 return -ECONNRESET; 1840 } 1841 errno = le16_to_cpu(msg->errno); 1842 if (errno) { 1843 rtrs_err(clt, "Invalid RTRS message: errno %d\n", 1844 errno); 1845 return -ECONNRESET; 1846 } 1847 if (con->c.cid == 0) { 1848 queue_depth = le16_to_cpu(msg->queue_depth); 1849 1850 if (clt_path->queue_depth > 0 && queue_depth != clt_path->queue_depth) { 1851 rtrs_err(clt, "Error: queue depth changed\n"); 1852 1853 /* 1854 * Stop any more reconnection attempts 1855 */ 1856 clt_path->reconnect_attempts = -1; 1857 rtrs_err(clt, 1858 "Disabling auto-reconnect. Trigger a manual reconnect after issue is resolved\n"); 1859 return -ECONNRESET; 1860 } 1861 1862 if (!clt_path->rbufs) { 1863 clt_path->rbufs = kcalloc(queue_depth, 1864 sizeof(*clt_path->rbufs), 1865 GFP_KERNEL); 1866 if (!clt_path->rbufs) 1867 return -ENOMEM; 1868 } 1869 clt_path->queue_depth = queue_depth; 1870 clt_path->s.signal_interval = min_not_zero(queue_depth, 1871 (unsigned short) SERVICE_CON_QUEUE_DEPTH); 1872 clt_path->max_hdr_size = le32_to_cpu(msg->max_hdr_size); 1873 clt_path->max_io_size = le32_to_cpu(msg->max_io_size); 1874 clt_path->flags = le32_to_cpu(msg->flags); 1875 clt_path->chunk_size = clt_path->max_io_size + clt_path->max_hdr_size; 1876 1877 /* 1878 * Global IO size is always a minimum. 1879 * If while a reconnection server sends us a value a bit 1880 * higher - client does not care and uses cached minimum. 1881 * 1882 * Since we can have several sessions (paths) restablishing 1883 * connections in parallel, use lock. 1884 */ 1885 mutex_lock(&clt->paths_mutex); 1886 clt->queue_depth = clt_path->queue_depth; 1887 clt->max_io_size = min_not_zero(clt_path->max_io_size, 1888 clt->max_io_size); 1889 mutex_unlock(&clt->paths_mutex); 1890 1891 /* 1892 * Cache the hca_port and hca_name for sysfs 1893 */ 1894 clt_path->hca_port = con->c.cm_id->port_num; 1895 scnprintf(clt_path->hca_name, sizeof(clt_path->hca_name), 1896 clt_path->s.dev->ib_dev->name); 1897 clt_path->s.src_addr = con->c.cm_id->route.addr.src_addr; 1898 /* set for_new_clt, to allow future reconnect on any path */ 1899 clt_path->for_new_clt = 1; 1900 } 1901 1902 return 0; 1903 } 1904 1905 static inline void flag_success_on_conn(struct rtrs_clt_con *con) 1906 { 1907 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 1908 1909 atomic_inc(&clt_path->connected_cnt); 1910 con->cm_err = 1; 1911 } 1912 1913 static int rtrs_rdma_conn_rejected(struct rtrs_clt_con *con, 1914 struct rdma_cm_event *ev) 1915 { 1916 struct rtrs_path *s = con->c.path; 1917 const struct rtrs_msg_conn_rsp *msg; 1918 const char *rej_msg; 1919 int status, errno; 1920 u8 data_len; 1921 1922 status = ev->status; 1923 rej_msg = rdma_reject_msg(con->c.cm_id, status); 1924 msg = rdma_consumer_reject_data(con->c.cm_id, ev, &data_len); 1925 1926 if (msg && data_len >= sizeof(*msg)) { 1927 errno = (int16_t)le16_to_cpu(msg->errno); 1928 if (errno == -EBUSY) 1929 rtrs_err(s, 1930 "Previous session is still exists on the server, please reconnect later\n"); 1931 else 1932 rtrs_err(s, 1933 "Connect rejected: status %d (%s), rtrs errno %d\n", 1934 status, rej_msg, errno); 1935 } else { 1936 rtrs_err(s, 1937 "Connect rejected but with malformed message: status %d (%s)\n", 1938 status, rej_msg); 1939 } 1940 1941 return -ECONNRESET; 1942 } 1943 1944 void rtrs_clt_close_conns(struct rtrs_clt_path *clt_path, bool wait) 1945 { 1946 if (rtrs_clt_change_state_get_old(clt_path, RTRS_CLT_CLOSING, NULL)) 1947 queue_work(rtrs_wq, &clt_path->close_work); 1948 if (wait) 1949 flush_work(&clt_path->close_work); 1950 } 1951 1952 static inline void flag_error_on_conn(struct rtrs_clt_con *con, int cm_err) 1953 { 1954 if (con->cm_err == 1) { 1955 struct rtrs_clt_path *clt_path; 1956 1957 clt_path = to_clt_path(con->c.path); 1958 if (atomic_dec_and_test(&clt_path->connected_cnt)) 1959 1960 wake_up(&clt_path->state_wq); 1961 } 1962 con->cm_err = cm_err; 1963 } 1964 1965 static int rtrs_clt_rdma_cm_handler(struct rdma_cm_id *cm_id, 1966 struct rdma_cm_event *ev) 1967 { 1968 struct rtrs_clt_con *con = cm_id->context; 1969 struct rtrs_path *s = con->c.path; 1970 struct rtrs_clt_path *clt_path = to_clt_path(s); 1971 int cm_err = 0; 1972 1973 switch (ev->event) { 1974 case RDMA_CM_EVENT_ADDR_RESOLVED: 1975 cm_err = rtrs_rdma_addr_resolved(con); 1976 break; 1977 case RDMA_CM_EVENT_ROUTE_RESOLVED: 1978 cm_err = rtrs_rdma_route_resolved(con); 1979 break; 1980 case RDMA_CM_EVENT_ESTABLISHED: 1981 cm_err = rtrs_rdma_conn_established(con, ev); 1982 if (!cm_err) { 1983 /* 1984 * Report success and wake up. Here we abuse state_wq, 1985 * i.e. wake up without state change, but we set cm_err. 1986 */ 1987 flag_success_on_conn(con); 1988 wake_up(&clt_path->state_wq); 1989 return 0; 1990 } 1991 break; 1992 case RDMA_CM_EVENT_REJECTED: 1993 cm_err = rtrs_rdma_conn_rejected(con, ev); 1994 break; 1995 case RDMA_CM_EVENT_DISCONNECTED: 1996 /* No message for disconnecting */ 1997 cm_err = -ECONNRESET; 1998 break; 1999 case RDMA_CM_EVENT_CONNECT_ERROR: 2000 case RDMA_CM_EVENT_UNREACHABLE: 2001 case RDMA_CM_EVENT_ADDR_CHANGE: 2002 case RDMA_CM_EVENT_TIMEWAIT_EXIT: 2003 rtrs_wrn(s, "CM error (CM event: %s, err: %d)\n", 2004 rdma_event_msg(ev->event), ev->status); 2005 cm_err = -ECONNRESET; 2006 break; 2007 case RDMA_CM_EVENT_ADDR_ERROR: 2008 case RDMA_CM_EVENT_ROUTE_ERROR: 2009 rtrs_wrn(s, "CM error (CM event: %s, err: %d)\n", 2010 rdma_event_msg(ev->event), ev->status); 2011 cm_err = -EHOSTUNREACH; 2012 break; 2013 case RDMA_CM_EVENT_DEVICE_REMOVAL: 2014 /* 2015 * Device removal is a special case. Queue close and return 0. 2016 */ 2017 rtrs_clt_close_conns(clt_path, false); 2018 return 0; 2019 default: 2020 rtrs_err(s, "Unexpected RDMA CM error (CM event: %s, err: %d)\n", 2021 rdma_event_msg(ev->event), ev->status); 2022 cm_err = -ECONNRESET; 2023 break; 2024 } 2025 2026 if (cm_err) { 2027 /* 2028 * cm error makes sense only on connection establishing, 2029 * in other cases we rely on normal procedure of reconnecting. 2030 */ 2031 flag_error_on_conn(con, cm_err); 2032 rtrs_rdma_error_recovery(con); 2033 } 2034 2035 return 0; 2036 } 2037 2038 static int create_cm(struct rtrs_clt_con *con) 2039 { 2040 struct rtrs_path *s = con->c.path; 2041 struct rtrs_clt_path *clt_path = to_clt_path(s); 2042 struct rdma_cm_id *cm_id; 2043 int err; 2044 2045 cm_id = rdma_create_id(&init_net, rtrs_clt_rdma_cm_handler, con, 2046 clt_path->s.dst_addr.ss_family == AF_IB ? 2047 RDMA_PS_IB : RDMA_PS_TCP, IB_QPT_RC); 2048 if (IS_ERR(cm_id)) { 2049 err = PTR_ERR(cm_id); 2050 rtrs_err(s, "Failed to create CM ID, err: %d\n", err); 2051 2052 return err; 2053 } 2054 con->c.cm_id = cm_id; 2055 con->cm_err = 0; 2056 /* allow the port to be reused */ 2057 err = rdma_set_reuseaddr(cm_id, 1); 2058 if (err != 0) { 2059 rtrs_err(s, "Set address reuse failed, err: %d\n", err); 2060 goto destroy_cm; 2061 } 2062 err = rdma_resolve_addr(cm_id, (struct sockaddr *)&clt_path->s.src_addr, 2063 (struct sockaddr *)&clt_path->s.dst_addr, 2064 RTRS_CONNECT_TIMEOUT_MS); 2065 if (err) { 2066 rtrs_err(s, "Failed to resolve address, err: %d\n", err); 2067 goto destroy_cm; 2068 } 2069 /* 2070 * Combine connection status and session events. This is needed 2071 * for waiting two possible cases: cm_err has something meaningful 2072 * or session state was really changed to error by device removal. 2073 */ 2074 err = wait_event_interruptible_timeout( 2075 clt_path->state_wq, 2076 con->cm_err || clt_path->state != RTRS_CLT_CONNECTING, 2077 msecs_to_jiffies(RTRS_CONNECT_TIMEOUT_MS)); 2078 if (err == 0 || err == -ERESTARTSYS) { 2079 if (err == 0) 2080 err = -ETIMEDOUT; 2081 /* Timedout or interrupted */ 2082 goto errr; 2083 } 2084 if (con->cm_err < 0) { 2085 err = con->cm_err; 2086 goto errr; 2087 } 2088 if (READ_ONCE(clt_path->state) != RTRS_CLT_CONNECTING) { 2089 /* Device removal */ 2090 err = -ECONNABORTED; 2091 goto errr; 2092 } 2093 2094 return 0; 2095 2096 errr: 2097 stop_cm(con); 2098 mutex_lock(&con->con_mutex); 2099 destroy_con_cq_qp(con); 2100 mutex_unlock(&con->con_mutex); 2101 destroy_cm: 2102 destroy_cm(con); 2103 2104 return err; 2105 } 2106 2107 static void rtrs_clt_path_up(struct rtrs_clt_path *clt_path) 2108 { 2109 struct rtrs_clt_sess *clt = clt_path->clt; 2110 int up; 2111 2112 /* 2113 * We can fire RECONNECTED event only when all paths were 2114 * connected on rtrs_clt_open(), then each was disconnected 2115 * and the first one connected again. That's why this nasty 2116 * game with counter value. 2117 */ 2118 2119 mutex_lock(&clt->paths_ev_mutex); 2120 up = ++clt->paths_up; 2121 /* 2122 * Here it is safe to access paths num directly since up counter 2123 * is greater than MAX_PATHS_NUM only while rtrs_clt_open() is 2124 * in progress, thus paths removals are impossible. 2125 */ 2126 if (up > MAX_PATHS_NUM && up == MAX_PATHS_NUM + clt->paths_num) 2127 clt->paths_up = clt->paths_num; 2128 else if (up == 1) 2129 clt->link_ev(clt->priv, RTRS_CLT_LINK_EV_RECONNECTED); 2130 mutex_unlock(&clt->paths_ev_mutex); 2131 2132 /* Mark session as established */ 2133 clt_path->established = true; 2134 clt_path->reconnect_attempts = 0; 2135 clt_path->stats->reconnects.successful_cnt++; 2136 } 2137 2138 static void rtrs_clt_path_down(struct rtrs_clt_path *clt_path) 2139 { 2140 struct rtrs_clt_sess *clt = clt_path->clt; 2141 2142 if (!clt_path->established) 2143 return; 2144 2145 clt_path->established = false; 2146 mutex_lock(&clt->paths_ev_mutex); 2147 WARN_ON(!clt->paths_up); 2148 if (--clt->paths_up == 0) 2149 clt->link_ev(clt->priv, RTRS_CLT_LINK_EV_DISCONNECTED); 2150 mutex_unlock(&clt->paths_ev_mutex); 2151 } 2152 2153 static void rtrs_clt_stop_and_destroy_conns(struct rtrs_clt_path *clt_path) 2154 { 2155 struct rtrs_clt_con *con; 2156 unsigned int cid; 2157 2158 WARN_ON(READ_ONCE(clt_path->state) == RTRS_CLT_CONNECTED); 2159 2160 /* 2161 * Possible race with rtrs_clt_open(), when DEVICE_REMOVAL comes 2162 * exactly in between. Start destroying after it finishes. 2163 */ 2164 mutex_lock(&clt_path->init_mutex); 2165 mutex_unlock(&clt_path->init_mutex); 2166 2167 /* 2168 * All IO paths must observe !CONNECTED state before we 2169 * free everything. 2170 */ 2171 synchronize_rcu(); 2172 2173 rtrs_stop_hb(&clt_path->s); 2174 2175 /* 2176 * The order it utterly crucial: firstly disconnect and complete all 2177 * rdma requests with error (thus set in_use=false for requests), 2178 * then fail outstanding requests checking in_use for each, and 2179 * eventually notify upper layer about session disconnection. 2180 */ 2181 2182 for (cid = 0; cid < clt_path->s.con_num; cid++) { 2183 if (!clt_path->s.con[cid]) 2184 break; 2185 con = to_clt_con(clt_path->s.con[cid]); 2186 stop_cm(con); 2187 } 2188 fail_all_outstanding_reqs(clt_path); 2189 free_path_reqs(clt_path); 2190 rtrs_clt_path_down(clt_path); 2191 2192 /* 2193 * Wait for graceful shutdown, namely when peer side invokes 2194 * rdma_disconnect(). 'connected_cnt' is decremented only on 2195 * CM events, thus if other side had crashed and hb has detected 2196 * something is wrong, here we will stuck for exactly timeout ms, 2197 * since CM does not fire anything. That is fine, we are not in 2198 * hurry. 2199 */ 2200 wait_event_timeout(clt_path->state_wq, 2201 !atomic_read(&clt_path->connected_cnt), 2202 msecs_to_jiffies(RTRS_CONNECT_TIMEOUT_MS)); 2203 2204 for (cid = 0; cid < clt_path->s.con_num; cid++) { 2205 if (!clt_path->s.con[cid]) 2206 break; 2207 con = to_clt_con(clt_path->s.con[cid]); 2208 mutex_lock(&con->con_mutex); 2209 destroy_con_cq_qp(con); 2210 mutex_unlock(&con->con_mutex); 2211 destroy_cm(con); 2212 destroy_con(con); 2213 } 2214 } 2215 2216 static inline bool xchg_paths(struct rtrs_clt_path __rcu **rcu_ppcpu_path, 2217 struct rtrs_clt_path *clt_path, 2218 struct rtrs_clt_path *next) 2219 { 2220 struct rtrs_clt_path **ppcpu_path; 2221 2222 /* Call cmpxchg() without sparse warnings */ 2223 ppcpu_path = (typeof(ppcpu_path))rcu_ppcpu_path; 2224 return clt_path == cmpxchg(ppcpu_path, clt_path, next); 2225 } 2226 2227 static void rtrs_clt_remove_path_from_arr(struct rtrs_clt_path *clt_path) 2228 { 2229 struct rtrs_clt_sess *clt = clt_path->clt; 2230 struct rtrs_clt_path *next; 2231 bool wait_for_grace = false; 2232 int cpu; 2233 2234 mutex_lock(&clt->paths_mutex); 2235 list_del_rcu(&clt_path->s.entry); 2236 2237 /* Make sure everybody observes path removal. */ 2238 synchronize_rcu(); 2239 2240 /* 2241 * At this point nobody sees @sess in the list, but still we have 2242 * dangling pointer @pcpu_path which _can_ point to @sess. Since 2243 * nobody can observe @sess in the list, we guarantee that IO path 2244 * will not assign @sess to @pcpu_path, i.e. @pcpu_path can be equal 2245 * to @sess, but can never again become @sess. 2246 */ 2247 2248 /* 2249 * Decrement paths number only after grace period, because 2250 * caller of do_each_path() must firstly observe list without 2251 * path and only then decremented paths number. 2252 * 2253 * Otherwise there can be the following situation: 2254 * o Two paths exist and IO is coming. 2255 * o One path is removed: 2256 * CPU#0 CPU#1 2257 * do_each_path(): rtrs_clt_remove_path_from_arr(): 2258 * path = get_next_path() 2259 * ^^^ list_del_rcu(path) 2260 * [!CONNECTED path] clt->paths_num-- 2261 * ^^^^^^^^^ 2262 * load clt->paths_num from 2 to 1 2263 * ^^^^^^^^^ 2264 * sees 1 2265 * 2266 * path is observed as !CONNECTED, but do_each_path() loop 2267 * ends, because expression i < clt->paths_num is false. 2268 */ 2269 clt->paths_num--; 2270 2271 /* 2272 * Get @next connection from current @sess which is going to be 2273 * removed. If @sess is the last element, then @next is NULL. 2274 */ 2275 rcu_read_lock(); 2276 next = rtrs_clt_get_next_path_or_null(&clt->paths_list, clt_path); 2277 rcu_read_unlock(); 2278 2279 /* 2280 * @pcpu paths can still point to the path which is going to be 2281 * removed, so change the pointer manually. 2282 */ 2283 for_each_possible_cpu(cpu) { 2284 struct rtrs_clt_path __rcu **ppcpu_path; 2285 2286 ppcpu_path = per_cpu_ptr(clt->pcpu_path, cpu); 2287 if (rcu_dereference_protected(*ppcpu_path, 2288 lockdep_is_held(&clt->paths_mutex)) != clt_path) 2289 /* 2290 * synchronize_rcu() was called just after deleting 2291 * entry from the list, thus IO code path cannot 2292 * change pointer back to the pointer which is going 2293 * to be removed, we are safe here. 2294 */ 2295 continue; 2296 2297 /* 2298 * We race with IO code path, which also changes pointer, 2299 * thus we have to be careful not to overwrite it. 2300 */ 2301 if (xchg_paths(ppcpu_path, clt_path, next)) 2302 /* 2303 * @ppcpu_path was successfully replaced with @next, 2304 * that means that someone could also pick up the 2305 * @sess and dereferencing it right now, so wait for 2306 * a grace period is required. 2307 */ 2308 wait_for_grace = true; 2309 } 2310 if (wait_for_grace) 2311 synchronize_rcu(); 2312 2313 mutex_unlock(&clt->paths_mutex); 2314 } 2315 2316 static void rtrs_clt_add_path_to_arr(struct rtrs_clt_path *clt_path) 2317 { 2318 struct rtrs_clt_sess *clt = clt_path->clt; 2319 2320 mutex_lock(&clt->paths_mutex); 2321 clt->paths_num++; 2322 2323 list_add_tail_rcu(&clt_path->s.entry, &clt->paths_list); 2324 mutex_unlock(&clt->paths_mutex); 2325 } 2326 2327 static void rtrs_clt_close_work(struct work_struct *work) 2328 { 2329 struct rtrs_clt_path *clt_path; 2330 2331 clt_path = container_of(work, struct rtrs_clt_path, close_work); 2332 2333 cancel_work_sync(&clt_path->err_recovery_work); 2334 cancel_delayed_work_sync(&clt_path->reconnect_dwork); 2335 rtrs_clt_stop_and_destroy_conns(clt_path); 2336 rtrs_clt_change_state_get_old(clt_path, RTRS_CLT_CLOSED, NULL); 2337 } 2338 2339 static int init_conns(struct rtrs_clt_path *clt_path) 2340 { 2341 unsigned int cid; 2342 int err; 2343 2344 /* 2345 * On every new session connections increase reconnect counter 2346 * to avoid clashes with previous sessions not yet closed 2347 * sessions on a server side. 2348 */ 2349 clt_path->s.recon_cnt++; 2350 2351 /* Establish all RDMA connections */ 2352 for (cid = 0; cid < clt_path->s.con_num; cid++) { 2353 err = create_con(clt_path, cid); 2354 if (err) 2355 goto destroy; 2356 2357 err = create_cm(to_clt_con(clt_path->s.con[cid])); 2358 if (err) { 2359 destroy_con(to_clt_con(clt_path->s.con[cid])); 2360 goto destroy; 2361 } 2362 } 2363 err = alloc_path_reqs(clt_path); 2364 if (err) 2365 goto destroy; 2366 2367 rtrs_start_hb(&clt_path->s); 2368 2369 return 0; 2370 2371 destroy: 2372 while (cid--) { 2373 struct rtrs_clt_con *con = to_clt_con(clt_path->s.con[cid]); 2374 2375 stop_cm(con); 2376 2377 mutex_lock(&con->con_mutex); 2378 destroy_con_cq_qp(con); 2379 mutex_unlock(&con->con_mutex); 2380 destroy_cm(con); 2381 destroy_con(con); 2382 } 2383 /* 2384 * If we've never taken async path and got an error, say, 2385 * doing rdma_resolve_addr(), switch to CONNECTION_ERR state 2386 * manually to keep reconnecting. 2387 */ 2388 rtrs_clt_change_state_get_old(clt_path, RTRS_CLT_CONNECTING_ERR, NULL); 2389 2390 return err; 2391 } 2392 2393 static void rtrs_clt_info_req_done(struct ib_cq *cq, struct ib_wc *wc) 2394 { 2395 struct rtrs_clt_con *con = to_clt_con(wc->qp->qp_context); 2396 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 2397 struct rtrs_iu *iu; 2398 2399 iu = container_of(wc->wr_cqe, struct rtrs_iu, cqe); 2400 rtrs_iu_free(iu, clt_path->s.dev->ib_dev, 1); 2401 2402 if (wc->status != IB_WC_SUCCESS) { 2403 rtrs_err(clt_path->clt, "Path info request send failed: %s\n", 2404 ib_wc_status_msg(wc->status)); 2405 rtrs_clt_change_state_get_old(clt_path, RTRS_CLT_CONNECTING_ERR, NULL); 2406 return; 2407 } 2408 2409 rtrs_clt_update_wc_stats(con); 2410 } 2411 2412 static int process_info_rsp(struct rtrs_clt_path *clt_path, 2413 const struct rtrs_msg_info_rsp *msg) 2414 { 2415 unsigned int sg_cnt, total_len; 2416 int i, sgi; 2417 2418 sg_cnt = le16_to_cpu(msg->sg_cnt); 2419 if (!sg_cnt || (clt_path->queue_depth % sg_cnt)) { 2420 rtrs_err(clt_path->clt, 2421 "Incorrect sg_cnt %d, is not multiple\n", 2422 sg_cnt); 2423 return -EINVAL; 2424 } 2425 2426 /* 2427 * Check if IB immediate data size is enough to hold the mem_id and 2428 * the offset inside the memory chunk. 2429 */ 2430 if ((ilog2(sg_cnt - 1) + 1) + (ilog2(clt_path->chunk_size - 1) + 1) > 2431 MAX_IMM_PAYL_BITS) { 2432 rtrs_err(clt_path->clt, 2433 "RDMA immediate size (%db) not enough to encode %d buffers of size %dB\n", 2434 MAX_IMM_PAYL_BITS, sg_cnt, clt_path->chunk_size); 2435 return -EINVAL; 2436 } 2437 total_len = 0; 2438 for (sgi = 0, i = 0; sgi < sg_cnt && i < clt_path->queue_depth; sgi++) { 2439 const struct rtrs_sg_desc *desc = &msg->desc[sgi]; 2440 u32 len, rkey; 2441 u64 addr; 2442 2443 addr = le64_to_cpu(desc->addr); 2444 rkey = le32_to_cpu(desc->key); 2445 len = le32_to_cpu(desc->len); 2446 2447 total_len += len; 2448 2449 if (!len || (len % clt_path->chunk_size)) { 2450 rtrs_err(clt_path->clt, "Incorrect [%d].len %d\n", 2451 sgi, 2452 len); 2453 return -EINVAL; 2454 } 2455 for ( ; len && i < clt_path->queue_depth; i++) { 2456 clt_path->rbufs[i].addr = addr; 2457 clt_path->rbufs[i].rkey = rkey; 2458 2459 len -= clt_path->chunk_size; 2460 addr += clt_path->chunk_size; 2461 } 2462 } 2463 /* Sanity check */ 2464 if (sgi != sg_cnt || i != clt_path->queue_depth) { 2465 rtrs_err(clt_path->clt, 2466 "Incorrect sg vector, not fully mapped\n"); 2467 return -EINVAL; 2468 } 2469 if (total_len != clt_path->chunk_size * clt_path->queue_depth) { 2470 rtrs_err(clt_path->clt, "Incorrect total_len %d\n", total_len); 2471 return -EINVAL; 2472 } 2473 2474 return 0; 2475 } 2476 2477 static void rtrs_clt_info_rsp_done(struct ib_cq *cq, struct ib_wc *wc) 2478 { 2479 struct rtrs_clt_con *con = to_clt_con(wc->qp->qp_context); 2480 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 2481 struct rtrs_msg_info_rsp *msg; 2482 enum rtrs_clt_state state; 2483 struct rtrs_iu *iu; 2484 size_t rx_sz; 2485 int err; 2486 2487 state = RTRS_CLT_CONNECTING_ERR; 2488 2489 WARN_ON(con->c.cid); 2490 iu = container_of(wc->wr_cqe, struct rtrs_iu, cqe); 2491 if (wc->status != IB_WC_SUCCESS) { 2492 rtrs_err(clt_path->clt, "Path info response recv failed: %s\n", 2493 ib_wc_status_msg(wc->status)); 2494 goto out; 2495 } 2496 WARN_ON(wc->opcode != IB_WC_RECV); 2497 2498 if (wc->byte_len < sizeof(*msg)) { 2499 rtrs_err(clt_path->clt, "Path info response is malformed: size %d\n", 2500 wc->byte_len); 2501 goto out; 2502 } 2503 ib_dma_sync_single_for_cpu(clt_path->s.dev->ib_dev, iu->dma_addr, 2504 iu->size, DMA_FROM_DEVICE); 2505 msg = iu->buf; 2506 if (le16_to_cpu(msg->type) != RTRS_MSG_INFO_RSP) { 2507 rtrs_err(clt_path->clt, "Path info response is malformed: type %d\n", 2508 le16_to_cpu(msg->type)); 2509 goto out; 2510 } 2511 rx_sz = sizeof(*msg); 2512 rx_sz += sizeof(msg->desc[0]) * le16_to_cpu(msg->sg_cnt); 2513 if (wc->byte_len < rx_sz) { 2514 rtrs_err(clt_path->clt, "Path info response is malformed: size %d\n", 2515 wc->byte_len); 2516 goto out; 2517 } 2518 err = process_info_rsp(clt_path, msg); 2519 if (err) 2520 goto out; 2521 2522 err = post_recv_path(clt_path); 2523 if (err) 2524 goto out; 2525 2526 state = RTRS_CLT_CONNECTED; 2527 2528 out: 2529 rtrs_clt_update_wc_stats(con); 2530 rtrs_iu_free(iu, clt_path->s.dev->ib_dev, 1); 2531 rtrs_clt_change_state_get_old(clt_path, state, NULL); 2532 } 2533 2534 static int rtrs_send_path_info(struct rtrs_clt_path *clt_path) 2535 { 2536 struct rtrs_clt_con *usr_con = to_clt_con(clt_path->s.con[0]); 2537 struct rtrs_msg_info_req *msg; 2538 struct rtrs_iu *tx_iu, *rx_iu; 2539 size_t rx_sz; 2540 int err; 2541 2542 rx_sz = sizeof(struct rtrs_msg_info_rsp); 2543 rx_sz += sizeof(struct rtrs_sg_desc) * clt_path->queue_depth; 2544 2545 tx_iu = rtrs_iu_alloc(1, sizeof(struct rtrs_msg_info_req), GFP_KERNEL, 2546 clt_path->s.dev->ib_dev, DMA_TO_DEVICE, 2547 rtrs_clt_info_req_done); 2548 rx_iu = rtrs_iu_alloc(1, rx_sz, GFP_KERNEL, clt_path->s.dev->ib_dev, 2549 DMA_FROM_DEVICE, rtrs_clt_info_rsp_done); 2550 if (!tx_iu || !rx_iu) { 2551 err = -ENOMEM; 2552 goto out; 2553 } 2554 /* Prepare for getting info response */ 2555 err = rtrs_iu_post_recv(&usr_con->c, rx_iu); 2556 if (err) { 2557 rtrs_err(clt_path->clt, "rtrs_iu_post_recv(), err: %d\n", err); 2558 goto out; 2559 } 2560 rx_iu = NULL; 2561 2562 msg = tx_iu->buf; 2563 msg->type = cpu_to_le16(RTRS_MSG_INFO_REQ); 2564 memcpy(msg->pathname, clt_path->s.sessname, sizeof(msg->pathname)); 2565 2566 ib_dma_sync_single_for_device(clt_path->s.dev->ib_dev, 2567 tx_iu->dma_addr, 2568 tx_iu->size, DMA_TO_DEVICE); 2569 2570 /* Send info request */ 2571 err = rtrs_iu_post_send(&usr_con->c, tx_iu, sizeof(*msg), NULL); 2572 if (err) { 2573 rtrs_err(clt_path->clt, "rtrs_iu_post_send(), err: %d\n", err); 2574 goto out; 2575 } 2576 tx_iu = NULL; 2577 2578 /* Wait for state change */ 2579 wait_event_interruptible_timeout(clt_path->state_wq, 2580 clt_path->state != RTRS_CLT_CONNECTING, 2581 msecs_to_jiffies( 2582 RTRS_CONNECT_TIMEOUT_MS)); 2583 if (READ_ONCE(clt_path->state) != RTRS_CLT_CONNECTED) { 2584 if (READ_ONCE(clt_path->state) == RTRS_CLT_CONNECTING_ERR) 2585 err = -ECONNRESET; 2586 else 2587 err = -ETIMEDOUT; 2588 } 2589 2590 out: 2591 if (tx_iu) 2592 rtrs_iu_free(tx_iu, clt_path->s.dev->ib_dev, 1); 2593 if (rx_iu) 2594 rtrs_iu_free(rx_iu, clt_path->s.dev->ib_dev, 1); 2595 if (err) 2596 /* If we've never taken async path because of malloc problems */ 2597 rtrs_clt_change_state_get_old(clt_path, 2598 RTRS_CLT_CONNECTING_ERR, NULL); 2599 2600 return err; 2601 } 2602 2603 /** 2604 * init_path() - establishes all path connections and does handshake 2605 * @clt_path: client path. 2606 * In case of error full close or reconnect procedure should be taken, 2607 * because reconnect or close async works can be started. 2608 */ 2609 static int init_path(struct rtrs_clt_path *clt_path) 2610 { 2611 int err; 2612 char str[NAME_MAX]; 2613 struct rtrs_addr path = { 2614 .src = &clt_path->s.src_addr, 2615 .dst = &clt_path->s.dst_addr, 2616 }; 2617 2618 rtrs_addr_to_str(&path, str, sizeof(str)); 2619 2620 mutex_lock(&clt_path->init_mutex); 2621 err = init_conns(clt_path); 2622 if (err) { 2623 rtrs_err(clt_path->clt, 2624 "init_conns() failed: err=%d path=%s [%s:%u]\n", err, 2625 str, clt_path->hca_name, clt_path->hca_port); 2626 goto out; 2627 } 2628 err = rtrs_send_path_info(clt_path); 2629 if (err) { 2630 rtrs_err(clt_path->clt, 2631 "rtrs_send_path_info() failed: err=%d path=%s [%s:%u]\n", 2632 err, str, clt_path->hca_name, clt_path->hca_port); 2633 goto out; 2634 } 2635 rtrs_clt_path_up(clt_path); 2636 out: 2637 mutex_unlock(&clt_path->init_mutex); 2638 2639 return err; 2640 } 2641 2642 static void rtrs_clt_reconnect_work(struct work_struct *work) 2643 { 2644 struct rtrs_clt_path *clt_path; 2645 struct rtrs_clt_sess *clt; 2646 int err; 2647 2648 clt_path = container_of(to_delayed_work(work), struct rtrs_clt_path, 2649 reconnect_dwork); 2650 clt = clt_path->clt; 2651 2652 if (READ_ONCE(clt_path->state) != RTRS_CLT_RECONNECTING) 2653 return; 2654 2655 if (clt_path->reconnect_attempts >= clt->max_reconnect_attempts) { 2656 /* Close a path completely if max attempts is reached */ 2657 rtrs_clt_close_conns(clt_path, false); 2658 return; 2659 } 2660 clt_path->reconnect_attempts++; 2661 2662 msleep(RTRS_RECONNECT_BACKOFF); 2663 if (rtrs_clt_change_state_get_old(clt_path, RTRS_CLT_CONNECTING, NULL)) { 2664 err = init_path(clt_path); 2665 if (err) 2666 goto reconnect_again; 2667 } 2668 2669 return; 2670 2671 reconnect_again: 2672 if (rtrs_clt_change_state_get_old(clt_path, RTRS_CLT_RECONNECTING, NULL)) { 2673 clt_path->stats->reconnects.fail_cnt++; 2674 queue_work(rtrs_wq, &clt_path->err_recovery_work); 2675 } 2676 } 2677 2678 static void rtrs_clt_dev_release(struct device *dev) 2679 { 2680 struct rtrs_clt_sess *clt = container_of(dev, struct rtrs_clt_sess, 2681 dev); 2682 2683 mutex_destroy(&clt->paths_ev_mutex); 2684 mutex_destroy(&clt->paths_mutex); 2685 kfree(clt); 2686 } 2687 2688 static struct rtrs_clt_sess *alloc_clt(const char *sessname, size_t paths_num, 2689 u16 port, size_t pdu_sz, void *priv, 2690 void (*link_ev)(void *priv, 2691 enum rtrs_clt_link_ev ev), 2692 unsigned int reconnect_delay_sec, 2693 unsigned int max_reconnect_attempts) 2694 { 2695 struct rtrs_clt_sess *clt; 2696 int err; 2697 2698 if (!paths_num || paths_num > MAX_PATHS_NUM) 2699 return ERR_PTR(-EINVAL); 2700 2701 if (strlen(sessname) >= sizeof(clt->sessname)) 2702 return ERR_PTR(-EINVAL); 2703 2704 clt = kzalloc(sizeof(*clt), GFP_KERNEL); 2705 if (!clt) 2706 return ERR_PTR(-ENOMEM); 2707 2708 clt->pcpu_path = alloc_percpu(typeof(*clt->pcpu_path)); 2709 if (!clt->pcpu_path) { 2710 kfree(clt); 2711 return ERR_PTR(-ENOMEM); 2712 } 2713 2714 clt->dev.class = rtrs_clt_dev_class; 2715 clt->dev.release = rtrs_clt_dev_release; 2716 uuid_gen(&clt->paths_uuid); 2717 INIT_LIST_HEAD_RCU(&clt->paths_list); 2718 clt->paths_num = paths_num; 2719 clt->paths_up = MAX_PATHS_NUM; 2720 clt->port = port; 2721 clt->pdu_sz = pdu_sz; 2722 clt->max_segments = RTRS_MAX_SEGMENTS; 2723 clt->reconnect_delay_sec = reconnect_delay_sec; 2724 clt->max_reconnect_attempts = max_reconnect_attempts; 2725 clt->priv = priv; 2726 clt->link_ev = link_ev; 2727 clt->mp_policy = MP_POLICY_MIN_INFLIGHT; 2728 strscpy(clt->sessname, sessname, sizeof(clt->sessname)); 2729 init_waitqueue_head(&clt->permits_wait); 2730 mutex_init(&clt->paths_ev_mutex); 2731 mutex_init(&clt->paths_mutex); 2732 device_initialize(&clt->dev); 2733 2734 err = dev_set_name(&clt->dev, "%s", sessname); 2735 if (err) 2736 goto err_put; 2737 2738 /* 2739 * Suppress user space notification until 2740 * sysfs files are created 2741 */ 2742 dev_set_uevent_suppress(&clt->dev, true); 2743 err = device_add(&clt->dev); 2744 if (err) 2745 goto err_put; 2746 2747 clt->kobj_paths = kobject_create_and_add("paths", &clt->dev.kobj); 2748 if (!clt->kobj_paths) { 2749 err = -ENOMEM; 2750 goto err_del; 2751 } 2752 err = rtrs_clt_create_sysfs_root_files(clt); 2753 if (err) { 2754 kobject_del(clt->kobj_paths); 2755 kobject_put(clt->kobj_paths); 2756 goto err_del; 2757 } 2758 dev_set_uevent_suppress(&clt->dev, false); 2759 kobject_uevent(&clt->dev.kobj, KOBJ_ADD); 2760 2761 return clt; 2762 err_del: 2763 device_del(&clt->dev); 2764 err_put: 2765 free_percpu(clt->pcpu_path); 2766 put_device(&clt->dev); 2767 return ERR_PTR(err); 2768 } 2769 2770 static void free_clt(struct rtrs_clt_sess *clt) 2771 { 2772 free_percpu(clt->pcpu_path); 2773 2774 /* 2775 * release callback will free clt and destroy mutexes in last put 2776 */ 2777 device_unregister(&clt->dev); 2778 } 2779 2780 /** 2781 * rtrs_clt_open() - Open a path to an RTRS server 2782 * @ops: holds the link event callback and the private pointer. 2783 * @pathname: name of the path to an RTRS server 2784 * @paths: Paths to be established defined by their src and dst addresses 2785 * @paths_num: Number of elements in the @paths array 2786 * @port: port to be used by the RTRS session 2787 * @pdu_sz: Size of extra payload which can be accessed after permit allocation. 2788 * @reconnect_delay_sec: time between reconnect tries 2789 * @max_reconnect_attempts: Number of times to reconnect on error before giving 2790 * up, 0 for * disabled, -1 for forever 2791 * @nr_poll_queues: number of polling mode connection using IB_POLL_DIRECT flag 2792 * 2793 * Starts session establishment with the rtrs_server. The function can block 2794 * up to ~2000ms before it returns. 2795 * 2796 * Return a valid pointer on success otherwise PTR_ERR. 2797 */ 2798 struct rtrs_clt_sess *rtrs_clt_open(struct rtrs_clt_ops *ops, 2799 const char *pathname, 2800 const struct rtrs_addr *paths, 2801 size_t paths_num, u16 port, 2802 size_t pdu_sz, u8 reconnect_delay_sec, 2803 s16 max_reconnect_attempts, u32 nr_poll_queues) 2804 { 2805 struct rtrs_clt_path *clt_path, *tmp; 2806 struct rtrs_clt_sess *clt; 2807 int err, i; 2808 2809 if (strchr(pathname, '/') || strchr(pathname, '.')) { 2810 pr_err("pathname cannot contain / and .\n"); 2811 err = -EINVAL; 2812 goto out; 2813 } 2814 2815 clt = alloc_clt(pathname, paths_num, port, pdu_sz, ops->priv, 2816 ops->link_ev, 2817 reconnect_delay_sec, 2818 max_reconnect_attempts); 2819 if (IS_ERR(clt)) { 2820 err = PTR_ERR(clt); 2821 goto out; 2822 } 2823 for (i = 0; i < paths_num; i++) { 2824 struct rtrs_clt_path *clt_path; 2825 2826 clt_path = alloc_path(clt, &paths[i], nr_cpu_ids, 2827 nr_poll_queues); 2828 if (IS_ERR(clt_path)) { 2829 err = PTR_ERR(clt_path); 2830 goto close_all_path; 2831 } 2832 if (!i) 2833 clt_path->for_new_clt = 1; 2834 list_add_tail_rcu(&clt_path->s.entry, &clt->paths_list); 2835 2836 err = init_path(clt_path); 2837 if (err) { 2838 list_del_rcu(&clt_path->s.entry); 2839 rtrs_clt_close_conns(clt_path, true); 2840 free_percpu(clt_path->stats->pcpu_stats); 2841 kfree(clt_path->stats); 2842 free_path(clt_path); 2843 goto close_all_path; 2844 } 2845 2846 err = rtrs_clt_create_path_files(clt_path); 2847 if (err) { 2848 list_del_rcu(&clt_path->s.entry); 2849 rtrs_clt_close_conns(clt_path, true); 2850 free_percpu(clt_path->stats->pcpu_stats); 2851 kfree(clt_path->stats); 2852 free_path(clt_path); 2853 goto close_all_path; 2854 } 2855 } 2856 err = alloc_permits(clt); 2857 if (err) 2858 goto close_all_path; 2859 2860 return clt; 2861 2862 close_all_path: 2863 list_for_each_entry_safe(clt_path, tmp, &clt->paths_list, s.entry) { 2864 rtrs_clt_destroy_path_files(clt_path, NULL); 2865 rtrs_clt_close_conns(clt_path, true); 2866 kobject_put(&clt_path->kobj); 2867 } 2868 rtrs_clt_destroy_sysfs_root(clt); 2869 free_clt(clt); 2870 2871 out: 2872 return ERR_PTR(err); 2873 } 2874 EXPORT_SYMBOL(rtrs_clt_open); 2875 2876 /** 2877 * rtrs_clt_close() - Close a path 2878 * @clt: Session handle. Session is freed upon return. 2879 */ 2880 void rtrs_clt_close(struct rtrs_clt_sess *clt) 2881 { 2882 struct rtrs_clt_path *clt_path, *tmp; 2883 2884 /* Firstly forbid sysfs access */ 2885 rtrs_clt_destroy_sysfs_root(clt); 2886 2887 /* Now it is safe to iterate over all paths without locks */ 2888 list_for_each_entry_safe(clt_path, tmp, &clt->paths_list, s.entry) { 2889 rtrs_clt_close_conns(clt_path, true); 2890 rtrs_clt_destroy_path_files(clt_path, NULL); 2891 kobject_put(&clt_path->kobj); 2892 } 2893 free_permits(clt); 2894 free_clt(clt); 2895 } 2896 EXPORT_SYMBOL(rtrs_clt_close); 2897 2898 int rtrs_clt_reconnect_from_sysfs(struct rtrs_clt_path *clt_path) 2899 { 2900 enum rtrs_clt_state old_state; 2901 int err = -EBUSY; 2902 bool changed; 2903 2904 changed = rtrs_clt_change_state_get_old(clt_path, 2905 RTRS_CLT_RECONNECTING, 2906 &old_state); 2907 if (changed) { 2908 clt_path->reconnect_attempts = 0; 2909 rtrs_clt_stop_and_destroy_conns(clt_path); 2910 queue_delayed_work(rtrs_wq, &clt_path->reconnect_dwork, 0); 2911 } 2912 if (changed || old_state == RTRS_CLT_RECONNECTING) { 2913 /* 2914 * flush_delayed_work() queues pending work for immediate 2915 * execution, so do the flush if we have queued something 2916 * right now or work is pending. 2917 */ 2918 flush_delayed_work(&clt_path->reconnect_dwork); 2919 err = (READ_ONCE(clt_path->state) == 2920 RTRS_CLT_CONNECTED ? 0 : -ENOTCONN); 2921 } 2922 2923 return err; 2924 } 2925 2926 int rtrs_clt_remove_path_from_sysfs(struct rtrs_clt_path *clt_path, 2927 const struct attribute *sysfs_self) 2928 { 2929 enum rtrs_clt_state old_state; 2930 bool changed; 2931 2932 /* 2933 * Continue stopping path till state was changed to DEAD or 2934 * state was observed as DEAD: 2935 * 1. State was changed to DEAD - we were fast and nobody 2936 * invoked rtrs_clt_reconnect(), which can again start 2937 * reconnecting. 2938 * 2. State was observed as DEAD - we have someone in parallel 2939 * removing the path. 2940 */ 2941 do { 2942 rtrs_clt_close_conns(clt_path, true); 2943 changed = rtrs_clt_change_state_get_old(clt_path, 2944 RTRS_CLT_DEAD, 2945 &old_state); 2946 } while (!changed && old_state != RTRS_CLT_DEAD); 2947 2948 if (changed) { 2949 rtrs_clt_remove_path_from_arr(clt_path); 2950 rtrs_clt_destroy_path_files(clt_path, sysfs_self); 2951 kobject_put(&clt_path->kobj); 2952 } 2953 2954 return 0; 2955 } 2956 2957 void rtrs_clt_set_max_reconnect_attempts(struct rtrs_clt_sess *clt, int value) 2958 { 2959 clt->max_reconnect_attempts = (unsigned int)value; 2960 } 2961 2962 int rtrs_clt_get_max_reconnect_attempts(const struct rtrs_clt_sess *clt) 2963 { 2964 return (int)clt->max_reconnect_attempts; 2965 } 2966 2967 /** 2968 * rtrs_clt_request() - Request data transfer to/from server via RDMA. 2969 * 2970 * @dir: READ/WRITE 2971 * @ops: callback function to be called as confirmation, and the pointer. 2972 * @clt: Session 2973 * @permit: Preallocated permit 2974 * @vec: Message that is sent to server together with the request. 2975 * Sum of len of all @vec elements limited to <= IO_MSG_SIZE. 2976 * Since the msg is copied internally it can be allocated on stack. 2977 * @nr: Number of elements in @vec. 2978 * @data_len: length of data sent to/from server 2979 * @sg: Pages to be sent/received to/from server. 2980 * @sg_cnt: Number of elements in the @sg 2981 * 2982 * Return: 2983 * 0: Success 2984 * <0: Error 2985 * 2986 * On dir=READ rtrs client will request a data transfer from Server to client. 2987 * The data that the server will respond with will be stored in @sg when 2988 * the user receives an %RTRS_CLT_RDMA_EV_RDMA_REQUEST_WRITE_COMPL event. 2989 * On dir=WRITE rtrs client will rdma write data in sg to server side. 2990 */ 2991 int rtrs_clt_request(int dir, struct rtrs_clt_req_ops *ops, 2992 struct rtrs_clt_sess *clt, struct rtrs_permit *permit, 2993 const struct kvec *vec, size_t nr, size_t data_len, 2994 struct scatterlist *sg, unsigned int sg_cnt) 2995 { 2996 struct rtrs_clt_io_req *req; 2997 struct rtrs_clt_path *clt_path; 2998 2999 enum dma_data_direction dma_dir; 3000 int err = -ECONNABORTED, i; 3001 size_t usr_len, hdr_len; 3002 struct path_it it; 3003 3004 /* Get kvec length */ 3005 for (i = 0, usr_len = 0; i < nr; i++) 3006 usr_len += vec[i].iov_len; 3007 3008 if (dir == READ) { 3009 hdr_len = sizeof(struct rtrs_msg_rdma_read) + 3010 sg_cnt * sizeof(struct rtrs_sg_desc); 3011 dma_dir = DMA_FROM_DEVICE; 3012 } else { 3013 hdr_len = sizeof(struct rtrs_msg_rdma_write); 3014 dma_dir = DMA_TO_DEVICE; 3015 } 3016 3017 rcu_read_lock(); 3018 for (path_it_init(&it, clt); 3019 (clt_path = it.next_path(&it)) && it.i < it.clt->paths_num; it.i++) { 3020 if (READ_ONCE(clt_path->state) != RTRS_CLT_CONNECTED) 3021 continue; 3022 3023 if (usr_len + hdr_len > clt_path->max_hdr_size) { 3024 rtrs_wrn_rl(clt_path->clt, 3025 "%s request failed, user message size is %zu and header length %zu, but max size is %u\n", 3026 dir == READ ? "Read" : "Write", 3027 usr_len, hdr_len, clt_path->max_hdr_size); 3028 err = -EMSGSIZE; 3029 break; 3030 } 3031 req = rtrs_clt_get_req(clt_path, ops->conf_fn, permit, ops->priv, 3032 vec, usr_len, sg, sg_cnt, data_len, 3033 dma_dir); 3034 if (dir == READ) 3035 err = rtrs_clt_read_req(req); 3036 else 3037 err = rtrs_clt_write_req(req); 3038 if (err) { 3039 req->in_use = false; 3040 continue; 3041 } 3042 /* Success path */ 3043 break; 3044 } 3045 path_it_deinit(&it); 3046 rcu_read_unlock(); 3047 3048 return err; 3049 } 3050 EXPORT_SYMBOL(rtrs_clt_request); 3051 3052 int rtrs_clt_rdma_cq_direct(struct rtrs_clt_sess *clt, unsigned int index) 3053 { 3054 /* If no path, return -1 for block layer not to try again */ 3055 int cnt = -1; 3056 struct rtrs_con *con; 3057 struct rtrs_clt_path *clt_path; 3058 struct path_it it; 3059 3060 rcu_read_lock(); 3061 for (path_it_init(&it, clt); 3062 (clt_path = it.next_path(&it)) && it.i < it.clt->paths_num; it.i++) { 3063 if (READ_ONCE(clt_path->state) != RTRS_CLT_CONNECTED) 3064 continue; 3065 3066 con = clt_path->s.con[index + 1]; 3067 cnt = ib_process_cq_direct(con->cq, -1); 3068 if (cnt) 3069 break; 3070 } 3071 path_it_deinit(&it); 3072 rcu_read_unlock(); 3073 3074 return cnt; 3075 } 3076 EXPORT_SYMBOL(rtrs_clt_rdma_cq_direct); 3077 3078 /** 3079 * rtrs_clt_query() - queries RTRS session attributes 3080 *@clt: session pointer 3081 *@attr: query results for session attributes. 3082 * Returns: 3083 * 0 on success 3084 * -ECOMM no connection to the server 3085 */ 3086 int rtrs_clt_query(struct rtrs_clt_sess *clt, struct rtrs_attrs *attr) 3087 { 3088 if (!rtrs_clt_is_connected(clt)) 3089 return -ECOMM; 3090 3091 attr->queue_depth = clt->queue_depth; 3092 attr->max_segments = clt->max_segments; 3093 /* Cap max_io_size to min of remote buffer size and the fr pages */ 3094 attr->max_io_size = min_t(int, clt->max_io_size, 3095 clt->max_segments * SZ_4K); 3096 3097 return 0; 3098 } 3099 EXPORT_SYMBOL(rtrs_clt_query); 3100 3101 int rtrs_clt_create_path_from_sysfs(struct rtrs_clt_sess *clt, 3102 struct rtrs_addr *addr) 3103 { 3104 struct rtrs_clt_path *clt_path; 3105 int err; 3106 3107 clt_path = alloc_path(clt, addr, nr_cpu_ids, 0); 3108 if (IS_ERR(clt_path)) 3109 return PTR_ERR(clt_path); 3110 3111 mutex_lock(&clt->paths_mutex); 3112 if (clt->paths_num == 0) { 3113 /* 3114 * When all the paths are removed for a session, 3115 * the addition of the first path is like a new session for 3116 * the storage server 3117 */ 3118 clt_path->for_new_clt = 1; 3119 } 3120 3121 mutex_unlock(&clt->paths_mutex); 3122 3123 /* 3124 * It is totally safe to add path in CONNECTING state: coming 3125 * IO will never grab it. Also it is very important to add 3126 * path before init, since init fires LINK_CONNECTED event. 3127 */ 3128 rtrs_clt_add_path_to_arr(clt_path); 3129 3130 err = init_path(clt_path); 3131 if (err) 3132 goto close_path; 3133 3134 err = rtrs_clt_create_path_files(clt_path); 3135 if (err) 3136 goto close_path; 3137 3138 return 0; 3139 3140 close_path: 3141 rtrs_clt_remove_path_from_arr(clt_path); 3142 rtrs_clt_close_conns(clt_path, true); 3143 free_percpu(clt_path->stats->pcpu_stats); 3144 kfree(clt_path->stats); 3145 free_path(clt_path); 3146 3147 return err; 3148 } 3149 3150 static int rtrs_clt_ib_dev_init(struct rtrs_ib_dev *dev) 3151 { 3152 if (!(dev->ib_dev->attrs.device_cap_flags & 3153 IB_DEVICE_MEM_MGT_EXTENSIONS)) { 3154 pr_err("Memory registrations not supported.\n"); 3155 return -ENOTSUPP; 3156 } 3157 3158 return 0; 3159 } 3160 3161 static const struct rtrs_rdma_dev_pd_ops dev_pd_ops = { 3162 .init = rtrs_clt_ib_dev_init 3163 }; 3164 3165 static int __init rtrs_client_init(void) 3166 { 3167 rtrs_rdma_dev_pd_init(0, &dev_pd); 3168 3169 rtrs_clt_dev_class = class_create(THIS_MODULE, "rtrs-client"); 3170 if (IS_ERR(rtrs_clt_dev_class)) { 3171 pr_err("Failed to create rtrs-client dev class\n"); 3172 return PTR_ERR(rtrs_clt_dev_class); 3173 } 3174 rtrs_wq = alloc_workqueue("rtrs_client_wq", 0, 0); 3175 if (!rtrs_wq) { 3176 class_destroy(rtrs_clt_dev_class); 3177 return -ENOMEM; 3178 } 3179 3180 return 0; 3181 } 3182 3183 static void __exit rtrs_client_exit(void) 3184 { 3185 destroy_workqueue(rtrs_wq); 3186 class_destroy(rtrs_clt_dev_class); 3187 rtrs_rdma_dev_pd_deinit(&dev_pd); 3188 } 3189 3190 module_init(rtrs_client_init); 3191 module_exit(rtrs_client_exit); 3192