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 * list_next_or_null_rr_rcu - get next list element in round-robin fashion. 745 * @head: the head for the list. 746 * @ptr: the list head to take the next element from. 747 * @type: the type of the struct this is embedded in. 748 * @memb: the name of the list_head within the struct. 749 * 750 * Next element returned in round-robin fashion, i.e. head will be skipped, 751 * but if list is observed as empty, NULL will be returned. 752 * 753 * This primitive may safely run concurrently with the _rcu list-mutation 754 * primitives such as list_add_rcu() as long as it's guarded by rcu_read_lock(). 755 */ 756 #define list_next_or_null_rr_rcu(head, ptr, type, memb) \ 757 ({ \ 758 list_next_or_null_rcu(head, ptr, type, memb) ?: \ 759 list_next_or_null_rcu(head, READ_ONCE((ptr)->next), \ 760 type, memb); \ 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 = list_next_or_null_rr_rcu(&clt->paths_list, 793 &path->s.entry, 794 typeof(*path), 795 s.entry); 796 rcu_assign_pointer(*ppcpu_path, path); 797 798 return path; 799 } 800 801 /** 802 * get_next_path_min_inflight() - Returns path with minimal inflight count. 803 * @it: the path pointer 804 * 805 * Related to @MP_POLICY_MIN_INFLIGHT 806 * 807 * Locks: 808 * rcu_read_lock() must be hold. 809 */ 810 static struct rtrs_clt_path *get_next_path_min_inflight(struct path_it *it) 811 { 812 struct rtrs_clt_path *min_path = NULL; 813 struct rtrs_clt_sess *clt = it->clt; 814 struct rtrs_clt_path *clt_path; 815 int min_inflight = INT_MAX; 816 int inflight; 817 818 list_for_each_entry_rcu(clt_path, &clt->paths_list, s.entry) { 819 if (READ_ONCE(clt_path->state) != RTRS_CLT_CONNECTED) 820 continue; 821 822 if (!list_empty(raw_cpu_ptr(clt_path->mp_skip_entry))) 823 continue; 824 825 inflight = atomic_read(&clt_path->stats->inflight); 826 827 if (inflight < min_inflight) { 828 min_inflight = inflight; 829 min_path = clt_path; 830 } 831 } 832 833 /* 834 * add the path to the skip list, so that next time we can get 835 * a different one 836 */ 837 if (min_path) 838 list_add(raw_cpu_ptr(min_path->mp_skip_entry), &it->skip_list); 839 840 return min_path; 841 } 842 843 /** 844 * get_next_path_min_latency() - Returns path with minimal latency. 845 * @it: the path pointer 846 * 847 * Return: a path with the lowest latency or NULL if all paths are tried 848 * 849 * Locks: 850 * rcu_read_lock() must be hold. 851 * 852 * Related to @MP_POLICY_MIN_LATENCY 853 * 854 * This DOES skip an already-tried path. 855 * There is a skip-list to skip a path if the path has tried but failed. 856 * It will try the minimum latency path and then the second minimum latency 857 * path and so on. Finally it will return NULL if all paths are tried. 858 * Therefore the caller MUST check the returned 859 * path is NULL and trigger the IO error. 860 */ 861 static struct rtrs_clt_path *get_next_path_min_latency(struct path_it *it) 862 { 863 struct rtrs_clt_path *min_path = NULL; 864 struct rtrs_clt_sess *clt = it->clt; 865 struct rtrs_clt_path *clt_path; 866 ktime_t min_latency = KTIME_MAX; 867 ktime_t latency; 868 869 list_for_each_entry_rcu(clt_path, &clt->paths_list, s.entry) { 870 if (READ_ONCE(clt_path->state) != RTRS_CLT_CONNECTED) 871 continue; 872 873 if (!list_empty(raw_cpu_ptr(clt_path->mp_skip_entry))) 874 continue; 875 876 latency = clt_path->s.hb_cur_latency; 877 878 if (latency < min_latency) { 879 min_latency = latency; 880 min_path = clt_path; 881 } 882 } 883 884 /* 885 * add the path to the skip list, so that next time we can get 886 * a different one 887 */ 888 if (min_path) 889 list_add(raw_cpu_ptr(min_path->mp_skip_entry), &it->skip_list); 890 891 return min_path; 892 } 893 894 static inline void path_it_init(struct path_it *it, struct rtrs_clt_sess *clt) 895 { 896 INIT_LIST_HEAD(&it->skip_list); 897 it->clt = clt; 898 it->i = 0; 899 900 if (clt->mp_policy == MP_POLICY_RR) 901 it->next_path = get_next_path_rr; 902 else if (clt->mp_policy == MP_POLICY_MIN_INFLIGHT) 903 it->next_path = get_next_path_min_inflight; 904 else 905 it->next_path = get_next_path_min_latency; 906 } 907 908 static inline void path_it_deinit(struct path_it *it) 909 { 910 struct list_head *skip, *tmp; 911 /* 912 * The skip_list is used only for the MIN_INFLIGHT and MIN_LATENCY policies. 913 * We need to remove paths from it, so that next IO can insert 914 * paths (->mp_skip_entry) into a skip_list again. 915 */ 916 list_for_each_safe(skip, tmp, &it->skip_list) 917 list_del_init(skip); 918 } 919 920 /** 921 * rtrs_clt_init_req() - Initialize an rtrs_clt_io_req holding information 922 * about an inflight IO. 923 * The user buffer holding user control message (not data) is copied into 924 * the corresponding buffer of rtrs_iu (req->iu->buf), which later on will 925 * also hold the control message of rtrs. 926 * @req: an io request holding information about IO. 927 * @clt_path: client path 928 * @conf: conformation callback function to notify upper layer. 929 * @permit: permit for allocation of RDMA remote buffer 930 * @priv: private pointer 931 * @vec: kernel vector containing control message 932 * @usr_len: length of the user message 933 * @sg: scater list for IO data 934 * @sg_cnt: number of scater list entries 935 * @data_len: length of the IO data 936 * @dir: direction of the IO. 937 */ 938 static void rtrs_clt_init_req(struct rtrs_clt_io_req *req, 939 struct rtrs_clt_path *clt_path, 940 void (*conf)(void *priv, int errno), 941 struct rtrs_permit *permit, void *priv, 942 const struct kvec *vec, size_t usr_len, 943 struct scatterlist *sg, size_t sg_cnt, 944 size_t data_len, int dir) 945 { 946 struct iov_iter iter; 947 size_t len; 948 949 req->permit = permit; 950 req->in_use = true; 951 req->usr_len = usr_len; 952 req->data_len = data_len; 953 req->sglist = sg; 954 req->sg_cnt = sg_cnt; 955 req->priv = priv; 956 req->dir = dir; 957 req->con = rtrs_permit_to_clt_con(clt_path, permit); 958 req->conf = conf; 959 req->need_inv = false; 960 req->need_inv_comp = false; 961 req->inv_errno = 0; 962 refcount_set(&req->ref, 1); 963 req->mp_policy = clt_path->clt->mp_policy; 964 965 iov_iter_kvec(&iter, READ, vec, 1, usr_len); 966 len = _copy_from_iter(req->iu->buf, usr_len, &iter); 967 WARN_ON(len != usr_len); 968 969 reinit_completion(&req->inv_comp); 970 } 971 972 static struct rtrs_clt_io_req * 973 rtrs_clt_get_req(struct rtrs_clt_path *clt_path, 974 void (*conf)(void *priv, int errno), 975 struct rtrs_permit *permit, void *priv, 976 const struct kvec *vec, size_t usr_len, 977 struct scatterlist *sg, size_t sg_cnt, 978 size_t data_len, int dir) 979 { 980 struct rtrs_clt_io_req *req; 981 982 req = &clt_path->reqs[permit->mem_id]; 983 rtrs_clt_init_req(req, clt_path, conf, permit, priv, vec, usr_len, 984 sg, sg_cnt, data_len, dir); 985 return req; 986 } 987 988 static struct rtrs_clt_io_req * 989 rtrs_clt_get_copy_req(struct rtrs_clt_path *alive_path, 990 struct rtrs_clt_io_req *fail_req) 991 { 992 struct rtrs_clt_io_req *req; 993 struct kvec vec = { 994 .iov_base = fail_req->iu->buf, 995 .iov_len = fail_req->usr_len 996 }; 997 998 req = &alive_path->reqs[fail_req->permit->mem_id]; 999 rtrs_clt_init_req(req, alive_path, fail_req->conf, fail_req->permit, 1000 fail_req->priv, &vec, fail_req->usr_len, 1001 fail_req->sglist, fail_req->sg_cnt, 1002 fail_req->data_len, fail_req->dir); 1003 return req; 1004 } 1005 1006 static int rtrs_post_rdma_write_sg(struct rtrs_clt_con *con, 1007 struct rtrs_clt_io_req *req, 1008 struct rtrs_rbuf *rbuf, bool fr_en, 1009 u32 size, u32 imm, struct ib_send_wr *wr, 1010 struct ib_send_wr *tail) 1011 { 1012 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 1013 struct ib_sge *sge = req->sge; 1014 enum ib_send_flags flags; 1015 struct scatterlist *sg; 1016 size_t num_sge; 1017 int i; 1018 struct ib_send_wr *ptail = NULL; 1019 1020 if (fr_en) { 1021 i = 0; 1022 sge[i].addr = req->mr->iova; 1023 sge[i].length = req->mr->length; 1024 sge[i].lkey = req->mr->lkey; 1025 i++; 1026 num_sge = 2; 1027 ptail = tail; 1028 } else { 1029 for_each_sg(req->sglist, sg, req->sg_cnt, i) { 1030 sge[i].addr = sg_dma_address(sg); 1031 sge[i].length = sg_dma_len(sg); 1032 sge[i].lkey = clt_path->s.dev->ib_pd->local_dma_lkey; 1033 } 1034 num_sge = 1 + req->sg_cnt; 1035 } 1036 sge[i].addr = req->iu->dma_addr; 1037 sge[i].length = size; 1038 sge[i].lkey = clt_path->s.dev->ib_pd->local_dma_lkey; 1039 1040 /* 1041 * From time to time we have to post signalled sends, 1042 * or send queue will fill up and only QP reset can help. 1043 */ 1044 flags = atomic_inc_return(&con->c.wr_cnt) % clt_path->s.signal_interval ? 1045 0 : IB_SEND_SIGNALED; 1046 1047 ib_dma_sync_single_for_device(clt_path->s.dev->ib_dev, 1048 req->iu->dma_addr, 1049 size, DMA_TO_DEVICE); 1050 1051 return rtrs_iu_post_rdma_write_imm(&con->c, req->iu, sge, num_sge, 1052 rbuf->rkey, rbuf->addr, imm, 1053 flags, wr, ptail); 1054 } 1055 1056 static int rtrs_map_sg_fr(struct rtrs_clt_io_req *req, size_t count) 1057 { 1058 int nr; 1059 1060 /* Align the MR to a 4K page size to match the block virt boundary */ 1061 nr = ib_map_mr_sg(req->mr, req->sglist, count, NULL, SZ_4K); 1062 if (nr < 0) 1063 return nr; 1064 if (nr < req->sg_cnt) 1065 return -EINVAL; 1066 ib_update_fast_reg_key(req->mr, ib_inc_rkey(req->mr->rkey)); 1067 1068 return nr; 1069 } 1070 1071 static int rtrs_clt_write_req(struct rtrs_clt_io_req *req) 1072 { 1073 struct rtrs_clt_con *con = req->con; 1074 struct rtrs_path *s = con->c.path; 1075 struct rtrs_clt_path *clt_path = to_clt_path(s); 1076 struct rtrs_msg_rdma_write *msg; 1077 1078 struct rtrs_rbuf *rbuf; 1079 int ret, count = 0; 1080 u32 imm, buf_id; 1081 struct ib_reg_wr rwr; 1082 struct ib_send_wr inv_wr; 1083 struct ib_send_wr *wr = NULL; 1084 bool fr_en = false; 1085 1086 const size_t tsize = sizeof(*msg) + req->data_len + req->usr_len; 1087 1088 if (tsize > clt_path->chunk_size) { 1089 rtrs_wrn(s, "Write request failed, size too big %zu > %d\n", 1090 tsize, clt_path->chunk_size); 1091 return -EMSGSIZE; 1092 } 1093 if (req->sg_cnt) { 1094 count = ib_dma_map_sg(clt_path->s.dev->ib_dev, req->sglist, 1095 req->sg_cnt, req->dir); 1096 if (!count) { 1097 rtrs_wrn(s, "Write request failed, map failed\n"); 1098 return -EINVAL; 1099 } 1100 } 1101 /* put rtrs msg after sg and user message */ 1102 msg = req->iu->buf + req->usr_len; 1103 msg->type = cpu_to_le16(RTRS_MSG_WRITE); 1104 msg->usr_len = cpu_to_le16(req->usr_len); 1105 1106 /* rtrs message on server side will be after user data and message */ 1107 imm = req->permit->mem_off + req->data_len + req->usr_len; 1108 imm = rtrs_to_io_req_imm(imm); 1109 buf_id = req->permit->mem_id; 1110 req->sg_size = tsize; 1111 rbuf = &clt_path->rbufs[buf_id]; 1112 1113 if (count) { 1114 ret = rtrs_map_sg_fr(req, count); 1115 if (ret < 0) { 1116 rtrs_err_rl(s, 1117 "Write request failed, failed to map fast reg. data, err: %d\n", 1118 ret); 1119 ib_dma_unmap_sg(clt_path->s.dev->ib_dev, req->sglist, 1120 req->sg_cnt, req->dir); 1121 return ret; 1122 } 1123 inv_wr = (struct ib_send_wr) { 1124 .opcode = IB_WR_LOCAL_INV, 1125 .wr_cqe = &req->inv_cqe, 1126 .send_flags = IB_SEND_SIGNALED, 1127 .ex.invalidate_rkey = req->mr->rkey, 1128 }; 1129 req->inv_cqe.done = rtrs_clt_inv_rkey_done; 1130 rwr = (struct ib_reg_wr) { 1131 .wr.opcode = IB_WR_REG_MR, 1132 .wr.wr_cqe = &fast_reg_cqe, 1133 .mr = req->mr, 1134 .key = req->mr->rkey, 1135 .access = (IB_ACCESS_LOCAL_WRITE), 1136 }; 1137 wr = &rwr.wr; 1138 fr_en = true; 1139 refcount_inc(&req->ref); 1140 } 1141 /* 1142 * Update stats now, after request is successfully sent it is not 1143 * safe anymore to touch it. 1144 */ 1145 rtrs_clt_update_all_stats(req, WRITE); 1146 1147 ret = rtrs_post_rdma_write_sg(req->con, req, rbuf, fr_en, 1148 req->usr_len + sizeof(*msg), 1149 imm, wr, &inv_wr); 1150 if (ret) { 1151 rtrs_err_rl(s, 1152 "Write request failed: error=%d path=%s [%s:%u]\n", 1153 ret, kobject_name(&clt_path->kobj), clt_path->hca_name, 1154 clt_path->hca_port); 1155 if (req->mp_policy == MP_POLICY_MIN_INFLIGHT) 1156 atomic_dec(&clt_path->stats->inflight); 1157 if (req->sg_cnt) 1158 ib_dma_unmap_sg(clt_path->s.dev->ib_dev, req->sglist, 1159 req->sg_cnt, req->dir); 1160 } 1161 1162 return ret; 1163 } 1164 1165 static int rtrs_clt_read_req(struct rtrs_clt_io_req *req) 1166 { 1167 struct rtrs_clt_con *con = req->con; 1168 struct rtrs_path *s = con->c.path; 1169 struct rtrs_clt_path *clt_path = to_clt_path(s); 1170 struct rtrs_msg_rdma_read *msg; 1171 struct rtrs_ib_dev *dev = clt_path->s.dev; 1172 1173 struct ib_reg_wr rwr; 1174 struct ib_send_wr *wr = NULL; 1175 1176 int ret, count = 0; 1177 u32 imm, buf_id; 1178 1179 const size_t tsize = sizeof(*msg) + req->data_len + req->usr_len; 1180 1181 if (tsize > clt_path->chunk_size) { 1182 rtrs_wrn(s, 1183 "Read request failed, message size is %zu, bigger than CHUNK_SIZE %d\n", 1184 tsize, clt_path->chunk_size); 1185 return -EMSGSIZE; 1186 } 1187 1188 if (req->sg_cnt) { 1189 count = ib_dma_map_sg(dev->ib_dev, req->sglist, req->sg_cnt, 1190 req->dir); 1191 if (!count) { 1192 rtrs_wrn(s, 1193 "Read request failed, dma map failed\n"); 1194 return -EINVAL; 1195 } 1196 } 1197 /* put our message into req->buf after user message*/ 1198 msg = req->iu->buf + req->usr_len; 1199 msg->type = cpu_to_le16(RTRS_MSG_READ); 1200 msg->usr_len = cpu_to_le16(req->usr_len); 1201 1202 if (count) { 1203 ret = rtrs_map_sg_fr(req, count); 1204 if (ret < 0) { 1205 rtrs_err_rl(s, 1206 "Read request failed, failed to map fast reg. data, err: %d\n", 1207 ret); 1208 ib_dma_unmap_sg(dev->ib_dev, req->sglist, req->sg_cnt, 1209 req->dir); 1210 return ret; 1211 } 1212 rwr = (struct ib_reg_wr) { 1213 .wr.opcode = IB_WR_REG_MR, 1214 .wr.wr_cqe = &fast_reg_cqe, 1215 .mr = req->mr, 1216 .key = req->mr->rkey, 1217 .access = (IB_ACCESS_LOCAL_WRITE | 1218 IB_ACCESS_REMOTE_WRITE), 1219 }; 1220 wr = &rwr.wr; 1221 1222 msg->sg_cnt = cpu_to_le16(1); 1223 msg->flags = cpu_to_le16(RTRS_MSG_NEED_INVAL_F); 1224 1225 msg->desc[0].addr = cpu_to_le64(req->mr->iova); 1226 msg->desc[0].key = cpu_to_le32(req->mr->rkey); 1227 msg->desc[0].len = cpu_to_le32(req->mr->length); 1228 1229 /* Further invalidation is required */ 1230 req->need_inv = !!RTRS_MSG_NEED_INVAL_F; 1231 1232 } else { 1233 msg->sg_cnt = 0; 1234 msg->flags = 0; 1235 } 1236 /* 1237 * rtrs message will be after the space reserved for disk data and 1238 * user message 1239 */ 1240 imm = req->permit->mem_off + req->data_len + req->usr_len; 1241 imm = rtrs_to_io_req_imm(imm); 1242 buf_id = req->permit->mem_id; 1243 1244 req->sg_size = sizeof(*msg); 1245 req->sg_size += le16_to_cpu(msg->sg_cnt) * sizeof(struct rtrs_sg_desc); 1246 req->sg_size += req->usr_len; 1247 1248 /* 1249 * Update stats now, after request is successfully sent it is not 1250 * safe anymore to touch it. 1251 */ 1252 rtrs_clt_update_all_stats(req, READ); 1253 1254 ret = rtrs_post_send_rdma(req->con, req, &clt_path->rbufs[buf_id], 1255 req->data_len, imm, wr); 1256 if (ret) { 1257 rtrs_err_rl(s, 1258 "Read request failed: error=%d path=%s [%s:%u]\n", 1259 ret, kobject_name(&clt_path->kobj), clt_path->hca_name, 1260 clt_path->hca_port); 1261 if (req->mp_policy == MP_POLICY_MIN_INFLIGHT) 1262 atomic_dec(&clt_path->stats->inflight); 1263 req->need_inv = false; 1264 if (req->sg_cnt) 1265 ib_dma_unmap_sg(dev->ib_dev, req->sglist, 1266 req->sg_cnt, req->dir); 1267 } 1268 1269 return ret; 1270 } 1271 1272 /** 1273 * rtrs_clt_failover_req() - Try to find an active path for a failed request 1274 * @clt: clt context 1275 * @fail_req: a failed io request. 1276 */ 1277 static int rtrs_clt_failover_req(struct rtrs_clt_sess *clt, 1278 struct rtrs_clt_io_req *fail_req) 1279 { 1280 struct rtrs_clt_path *alive_path; 1281 struct rtrs_clt_io_req *req; 1282 int err = -ECONNABORTED; 1283 struct path_it it; 1284 1285 rcu_read_lock(); 1286 for (path_it_init(&it, clt); 1287 (alive_path = it.next_path(&it)) && it.i < it.clt->paths_num; 1288 it.i++) { 1289 if (READ_ONCE(alive_path->state) != RTRS_CLT_CONNECTED) 1290 continue; 1291 req = rtrs_clt_get_copy_req(alive_path, fail_req); 1292 if (req->dir == DMA_TO_DEVICE) 1293 err = rtrs_clt_write_req(req); 1294 else 1295 err = rtrs_clt_read_req(req); 1296 if (err) { 1297 req->in_use = false; 1298 continue; 1299 } 1300 /* Success path */ 1301 rtrs_clt_inc_failover_cnt(alive_path->stats); 1302 break; 1303 } 1304 path_it_deinit(&it); 1305 rcu_read_unlock(); 1306 1307 return err; 1308 } 1309 1310 static void fail_all_outstanding_reqs(struct rtrs_clt_path *clt_path) 1311 { 1312 struct rtrs_clt_sess *clt = clt_path->clt; 1313 struct rtrs_clt_io_req *req; 1314 int i, err; 1315 1316 if (!clt_path->reqs) 1317 return; 1318 for (i = 0; i < clt_path->queue_depth; ++i) { 1319 req = &clt_path->reqs[i]; 1320 if (!req->in_use) 1321 continue; 1322 1323 /* 1324 * Safely (without notification) complete failed request. 1325 * After completion this request is still useble and can 1326 * be failovered to another path. 1327 */ 1328 complete_rdma_req(req, -ECONNABORTED, false, true); 1329 1330 err = rtrs_clt_failover_req(clt, req); 1331 if (err) 1332 /* Failover failed, notify anyway */ 1333 req->conf(req->priv, err); 1334 } 1335 } 1336 1337 static void free_path_reqs(struct rtrs_clt_path *clt_path) 1338 { 1339 struct rtrs_clt_io_req *req; 1340 int i; 1341 1342 if (!clt_path->reqs) 1343 return; 1344 for (i = 0; i < clt_path->queue_depth; ++i) { 1345 req = &clt_path->reqs[i]; 1346 if (req->mr) 1347 ib_dereg_mr(req->mr); 1348 kfree(req->sge); 1349 rtrs_iu_free(req->iu, clt_path->s.dev->ib_dev, 1); 1350 } 1351 kfree(clt_path->reqs); 1352 clt_path->reqs = NULL; 1353 } 1354 1355 static int alloc_path_reqs(struct rtrs_clt_path *clt_path) 1356 { 1357 struct rtrs_clt_io_req *req; 1358 int i, err = -ENOMEM; 1359 1360 clt_path->reqs = kcalloc(clt_path->queue_depth, 1361 sizeof(*clt_path->reqs), 1362 GFP_KERNEL); 1363 if (!clt_path->reqs) 1364 return -ENOMEM; 1365 1366 for (i = 0; i < clt_path->queue_depth; ++i) { 1367 req = &clt_path->reqs[i]; 1368 req->iu = rtrs_iu_alloc(1, clt_path->max_hdr_size, GFP_KERNEL, 1369 clt_path->s.dev->ib_dev, 1370 DMA_TO_DEVICE, 1371 rtrs_clt_rdma_done); 1372 if (!req->iu) 1373 goto out; 1374 1375 req->sge = kcalloc(2, sizeof(*req->sge), GFP_KERNEL); 1376 if (!req->sge) 1377 goto out; 1378 1379 req->mr = ib_alloc_mr(clt_path->s.dev->ib_pd, 1380 IB_MR_TYPE_MEM_REG, 1381 clt_path->max_pages_per_mr); 1382 if (IS_ERR(req->mr)) { 1383 err = PTR_ERR(req->mr); 1384 req->mr = NULL; 1385 pr_err("Failed to alloc clt_path->max_pages_per_mr %d\n", 1386 clt_path->max_pages_per_mr); 1387 goto out; 1388 } 1389 1390 init_completion(&req->inv_comp); 1391 } 1392 1393 return 0; 1394 1395 out: 1396 free_path_reqs(clt_path); 1397 1398 return err; 1399 } 1400 1401 static int alloc_permits(struct rtrs_clt_sess *clt) 1402 { 1403 unsigned int chunk_bits; 1404 int err, i; 1405 1406 clt->permits_map = kcalloc(BITS_TO_LONGS(clt->queue_depth), 1407 sizeof(long), GFP_KERNEL); 1408 if (!clt->permits_map) { 1409 err = -ENOMEM; 1410 goto out_err; 1411 } 1412 clt->permits = kcalloc(clt->queue_depth, permit_size(clt), GFP_KERNEL); 1413 if (!clt->permits) { 1414 err = -ENOMEM; 1415 goto err_map; 1416 } 1417 chunk_bits = ilog2(clt->queue_depth - 1) + 1; 1418 for (i = 0; i < clt->queue_depth; i++) { 1419 struct rtrs_permit *permit; 1420 1421 permit = get_permit(clt, i); 1422 permit->mem_id = i; 1423 permit->mem_off = i << (MAX_IMM_PAYL_BITS - chunk_bits); 1424 } 1425 1426 return 0; 1427 1428 err_map: 1429 kfree(clt->permits_map); 1430 clt->permits_map = NULL; 1431 out_err: 1432 return err; 1433 } 1434 1435 static void free_permits(struct rtrs_clt_sess *clt) 1436 { 1437 if (clt->permits_map) { 1438 size_t sz = clt->queue_depth; 1439 1440 wait_event(clt->permits_wait, 1441 find_first_bit(clt->permits_map, sz) >= sz); 1442 } 1443 kfree(clt->permits_map); 1444 clt->permits_map = NULL; 1445 kfree(clt->permits); 1446 clt->permits = NULL; 1447 } 1448 1449 static void query_fast_reg_mode(struct rtrs_clt_path *clt_path) 1450 { 1451 struct ib_device *ib_dev; 1452 u64 max_pages_per_mr; 1453 int mr_page_shift; 1454 1455 ib_dev = clt_path->s.dev->ib_dev; 1456 1457 /* 1458 * Use the smallest page size supported by the HCA, down to a 1459 * minimum of 4096 bytes. We're unlikely to build large sglists 1460 * out of smaller entries. 1461 */ 1462 mr_page_shift = max(12, ffs(ib_dev->attrs.page_size_cap) - 1); 1463 max_pages_per_mr = ib_dev->attrs.max_mr_size; 1464 do_div(max_pages_per_mr, (1ull << mr_page_shift)); 1465 clt_path->max_pages_per_mr = 1466 min3(clt_path->max_pages_per_mr, (u32)max_pages_per_mr, 1467 ib_dev->attrs.max_fast_reg_page_list_len); 1468 clt_path->clt->max_segments = 1469 min(clt_path->max_pages_per_mr, clt_path->clt->max_segments); 1470 } 1471 1472 static bool rtrs_clt_change_state_get_old(struct rtrs_clt_path *clt_path, 1473 enum rtrs_clt_state new_state, 1474 enum rtrs_clt_state *old_state) 1475 { 1476 bool changed; 1477 1478 spin_lock_irq(&clt_path->state_wq.lock); 1479 if (old_state) 1480 *old_state = clt_path->state; 1481 changed = rtrs_clt_change_state(clt_path, new_state); 1482 spin_unlock_irq(&clt_path->state_wq.lock); 1483 1484 return changed; 1485 } 1486 1487 static void rtrs_clt_hb_err_handler(struct rtrs_con *c) 1488 { 1489 struct rtrs_clt_con *con = container_of(c, typeof(*con), c); 1490 1491 rtrs_rdma_error_recovery(con); 1492 } 1493 1494 static void rtrs_clt_init_hb(struct rtrs_clt_path *clt_path) 1495 { 1496 rtrs_init_hb(&clt_path->s, &io_comp_cqe, 1497 RTRS_HB_INTERVAL_MS, 1498 RTRS_HB_MISSED_MAX, 1499 rtrs_clt_hb_err_handler, 1500 rtrs_wq); 1501 } 1502 1503 static void rtrs_clt_reconnect_work(struct work_struct *work); 1504 static void rtrs_clt_close_work(struct work_struct *work); 1505 1506 static void rtrs_clt_err_recovery_work(struct work_struct *work) 1507 { 1508 struct rtrs_clt_path *clt_path; 1509 struct rtrs_clt_sess *clt; 1510 int delay_ms; 1511 1512 clt_path = container_of(work, struct rtrs_clt_path, err_recovery_work); 1513 clt = clt_path->clt; 1514 delay_ms = clt->reconnect_delay_sec * 1000; 1515 rtrs_clt_stop_and_destroy_conns(clt_path); 1516 queue_delayed_work(rtrs_wq, &clt_path->reconnect_dwork, 1517 msecs_to_jiffies(delay_ms + 1518 prandom_u32() % 1519 RTRS_RECONNECT_SEED)); 1520 } 1521 1522 static struct rtrs_clt_path *alloc_path(struct rtrs_clt_sess *clt, 1523 const struct rtrs_addr *path, 1524 size_t con_num, u32 nr_poll_queues) 1525 { 1526 struct rtrs_clt_path *clt_path; 1527 int err = -ENOMEM; 1528 int cpu; 1529 size_t total_con; 1530 1531 clt_path = kzalloc(sizeof(*clt_path), GFP_KERNEL); 1532 if (!clt_path) 1533 goto err; 1534 1535 /* 1536 * irqmode and poll 1537 * +1: Extra connection for user messages 1538 */ 1539 total_con = con_num + nr_poll_queues + 1; 1540 clt_path->s.con = kcalloc(total_con, sizeof(*clt_path->s.con), 1541 GFP_KERNEL); 1542 if (!clt_path->s.con) 1543 goto err_free_path; 1544 1545 clt_path->s.con_num = total_con; 1546 clt_path->s.irq_con_num = con_num + 1; 1547 1548 clt_path->stats = kzalloc(sizeof(*clt_path->stats), GFP_KERNEL); 1549 if (!clt_path->stats) 1550 goto err_free_con; 1551 1552 mutex_init(&clt_path->init_mutex); 1553 uuid_gen(&clt_path->s.uuid); 1554 memcpy(&clt_path->s.dst_addr, path->dst, 1555 rdma_addr_size((struct sockaddr *)path->dst)); 1556 1557 /* 1558 * rdma_resolve_addr() passes src_addr to cma_bind_addr, which 1559 * checks the sa_family to be non-zero. If user passed src_addr=NULL 1560 * the sess->src_addr will contain only zeros, which is then fine. 1561 */ 1562 if (path->src) 1563 memcpy(&clt_path->s.src_addr, path->src, 1564 rdma_addr_size((struct sockaddr *)path->src)); 1565 strscpy(clt_path->s.sessname, clt->sessname, 1566 sizeof(clt_path->s.sessname)); 1567 clt_path->clt = clt; 1568 clt_path->max_pages_per_mr = RTRS_MAX_SEGMENTS; 1569 init_waitqueue_head(&clt_path->state_wq); 1570 clt_path->state = RTRS_CLT_CONNECTING; 1571 atomic_set(&clt_path->connected_cnt, 0); 1572 INIT_WORK(&clt_path->close_work, rtrs_clt_close_work); 1573 INIT_WORK(&clt_path->err_recovery_work, rtrs_clt_err_recovery_work); 1574 INIT_DELAYED_WORK(&clt_path->reconnect_dwork, rtrs_clt_reconnect_work); 1575 rtrs_clt_init_hb(clt_path); 1576 1577 clt_path->mp_skip_entry = alloc_percpu(typeof(*clt_path->mp_skip_entry)); 1578 if (!clt_path->mp_skip_entry) 1579 goto err_free_stats; 1580 1581 for_each_possible_cpu(cpu) 1582 INIT_LIST_HEAD(per_cpu_ptr(clt_path->mp_skip_entry, cpu)); 1583 1584 err = rtrs_clt_init_stats(clt_path->stats); 1585 if (err) 1586 goto err_free_percpu; 1587 1588 return clt_path; 1589 1590 err_free_percpu: 1591 free_percpu(clt_path->mp_skip_entry); 1592 err_free_stats: 1593 kfree(clt_path->stats); 1594 err_free_con: 1595 kfree(clt_path->s.con); 1596 err_free_path: 1597 kfree(clt_path); 1598 err: 1599 return ERR_PTR(err); 1600 } 1601 1602 void free_path(struct rtrs_clt_path *clt_path) 1603 { 1604 free_percpu(clt_path->mp_skip_entry); 1605 mutex_destroy(&clt_path->init_mutex); 1606 kfree(clt_path->s.con); 1607 kfree(clt_path->rbufs); 1608 kfree(clt_path); 1609 } 1610 1611 static int create_con(struct rtrs_clt_path *clt_path, unsigned int cid) 1612 { 1613 struct rtrs_clt_con *con; 1614 1615 con = kzalloc(sizeof(*con), GFP_KERNEL); 1616 if (!con) 1617 return -ENOMEM; 1618 1619 /* Map first two connections to the first CPU */ 1620 con->cpu = (cid ? cid - 1 : 0) % nr_cpu_ids; 1621 con->c.cid = cid; 1622 con->c.path = &clt_path->s; 1623 /* Align with srv, init as 1 */ 1624 atomic_set(&con->c.wr_cnt, 1); 1625 mutex_init(&con->con_mutex); 1626 1627 clt_path->s.con[cid] = &con->c; 1628 1629 return 0; 1630 } 1631 1632 static void destroy_con(struct rtrs_clt_con *con) 1633 { 1634 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 1635 1636 clt_path->s.con[con->c.cid] = NULL; 1637 mutex_destroy(&con->con_mutex); 1638 kfree(con); 1639 } 1640 1641 static int create_con_cq_qp(struct rtrs_clt_con *con) 1642 { 1643 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 1644 u32 max_send_wr, max_recv_wr, cq_num, max_send_sge, wr_limit; 1645 int err, cq_vector; 1646 struct rtrs_msg_rkey_rsp *rsp; 1647 1648 lockdep_assert_held(&con->con_mutex); 1649 if (con->c.cid == 0) { 1650 max_send_sge = 1; 1651 /* We must be the first here */ 1652 if (WARN_ON(clt_path->s.dev)) 1653 return -EINVAL; 1654 1655 /* 1656 * The whole session uses device from user connection. 1657 * Be careful not to close user connection before ib dev 1658 * is gracefully put. 1659 */ 1660 clt_path->s.dev = rtrs_ib_dev_find_or_add(con->c.cm_id->device, 1661 &dev_pd); 1662 if (!clt_path->s.dev) { 1663 rtrs_wrn(clt_path->clt, 1664 "rtrs_ib_dev_find_get_or_add(): no memory\n"); 1665 return -ENOMEM; 1666 } 1667 clt_path->s.dev_ref = 1; 1668 query_fast_reg_mode(clt_path); 1669 wr_limit = clt_path->s.dev->ib_dev->attrs.max_qp_wr; 1670 /* 1671 * Two (request + registration) completion for send 1672 * Two for recv if always_invalidate is set on server 1673 * or one for recv. 1674 * + 2 for drain and heartbeat 1675 * in case qp gets into error state. 1676 */ 1677 max_send_wr = 1678 min_t(int, wr_limit, SERVICE_CON_QUEUE_DEPTH * 2 + 2); 1679 max_recv_wr = max_send_wr; 1680 } else { 1681 /* 1682 * Here we assume that session members are correctly set. 1683 * This is always true if user connection (cid == 0) is 1684 * established first. 1685 */ 1686 if (WARN_ON(!clt_path->s.dev)) 1687 return -EINVAL; 1688 if (WARN_ON(!clt_path->queue_depth)) 1689 return -EINVAL; 1690 1691 wr_limit = clt_path->s.dev->ib_dev->attrs.max_qp_wr; 1692 /* Shared between connections */ 1693 clt_path->s.dev_ref++; 1694 max_send_wr = min_t(int, wr_limit, 1695 /* QD * (REQ + RSP + FR REGS or INVS) + drain */ 1696 clt_path->queue_depth * 3 + 1); 1697 max_recv_wr = min_t(int, wr_limit, 1698 clt_path->queue_depth * 3 + 1); 1699 max_send_sge = 2; 1700 } 1701 atomic_set(&con->c.sq_wr_avail, max_send_wr); 1702 cq_num = max_send_wr + max_recv_wr; 1703 /* alloc iu to recv new rkey reply when server reports flags set */ 1704 if (clt_path->flags & RTRS_MSG_NEW_RKEY_F || con->c.cid == 0) { 1705 con->rsp_ius = rtrs_iu_alloc(cq_num, sizeof(*rsp), 1706 GFP_KERNEL, 1707 clt_path->s.dev->ib_dev, 1708 DMA_FROM_DEVICE, 1709 rtrs_clt_rdma_done); 1710 if (!con->rsp_ius) 1711 return -ENOMEM; 1712 con->queue_num = cq_num; 1713 } 1714 cq_num = max_send_wr + max_recv_wr; 1715 cq_vector = con->cpu % clt_path->s.dev->ib_dev->num_comp_vectors; 1716 if (con->c.cid >= clt_path->s.irq_con_num) 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_DIRECT); 1720 else 1721 err = rtrs_cq_qp_create(&clt_path->s, &con->c, max_send_sge, 1722 cq_vector, cq_num, max_send_wr, 1723 max_recv_wr, IB_POLL_SOFTIRQ); 1724 /* 1725 * In case of error we do not bother to clean previous allocations, 1726 * since destroy_con_cq_qp() must be called. 1727 */ 1728 return err; 1729 } 1730 1731 static void destroy_con_cq_qp(struct rtrs_clt_con *con) 1732 { 1733 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 1734 1735 /* 1736 * Be careful here: destroy_con_cq_qp() can be called even 1737 * create_con_cq_qp() failed, see comments there. 1738 */ 1739 lockdep_assert_held(&con->con_mutex); 1740 rtrs_cq_qp_destroy(&con->c); 1741 if (con->rsp_ius) { 1742 rtrs_iu_free(con->rsp_ius, clt_path->s.dev->ib_dev, 1743 con->queue_num); 1744 con->rsp_ius = NULL; 1745 con->queue_num = 0; 1746 } 1747 if (clt_path->s.dev_ref && !--clt_path->s.dev_ref) { 1748 rtrs_ib_dev_put(clt_path->s.dev); 1749 clt_path->s.dev = NULL; 1750 } 1751 } 1752 1753 static void stop_cm(struct rtrs_clt_con *con) 1754 { 1755 rdma_disconnect(con->c.cm_id); 1756 if (con->c.qp) 1757 ib_drain_qp(con->c.qp); 1758 } 1759 1760 static void destroy_cm(struct rtrs_clt_con *con) 1761 { 1762 rdma_destroy_id(con->c.cm_id); 1763 con->c.cm_id = NULL; 1764 } 1765 1766 static int rtrs_rdma_addr_resolved(struct rtrs_clt_con *con) 1767 { 1768 struct rtrs_path *s = con->c.path; 1769 int err; 1770 1771 mutex_lock(&con->con_mutex); 1772 err = create_con_cq_qp(con); 1773 mutex_unlock(&con->con_mutex); 1774 if (err) { 1775 rtrs_err(s, "create_con_cq_qp(), err: %d\n", err); 1776 return err; 1777 } 1778 err = rdma_resolve_route(con->c.cm_id, RTRS_CONNECT_TIMEOUT_MS); 1779 if (err) 1780 rtrs_err(s, "Resolving route failed, err: %d\n", err); 1781 1782 return err; 1783 } 1784 1785 static int rtrs_rdma_route_resolved(struct rtrs_clt_con *con) 1786 { 1787 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 1788 struct rtrs_clt_sess *clt = clt_path->clt; 1789 struct rtrs_msg_conn_req msg; 1790 struct rdma_conn_param param; 1791 1792 int err; 1793 1794 param = (struct rdma_conn_param) { 1795 .retry_count = 7, 1796 .rnr_retry_count = 7, 1797 .private_data = &msg, 1798 .private_data_len = sizeof(msg), 1799 }; 1800 1801 msg = (struct rtrs_msg_conn_req) { 1802 .magic = cpu_to_le16(RTRS_MAGIC), 1803 .version = cpu_to_le16(RTRS_PROTO_VER), 1804 .cid = cpu_to_le16(con->c.cid), 1805 .cid_num = cpu_to_le16(clt_path->s.con_num), 1806 .recon_cnt = cpu_to_le16(clt_path->s.recon_cnt), 1807 }; 1808 msg.first_conn = clt_path->for_new_clt ? FIRST_CONN : 0; 1809 uuid_copy(&msg.sess_uuid, &clt_path->s.uuid); 1810 uuid_copy(&msg.paths_uuid, &clt->paths_uuid); 1811 1812 err = rdma_connect_locked(con->c.cm_id, ¶m); 1813 if (err) 1814 rtrs_err(clt, "rdma_connect_locked(): %d\n", err); 1815 1816 return err; 1817 } 1818 1819 static int rtrs_rdma_conn_established(struct rtrs_clt_con *con, 1820 struct rdma_cm_event *ev) 1821 { 1822 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 1823 struct rtrs_clt_sess *clt = clt_path->clt; 1824 const struct rtrs_msg_conn_rsp *msg; 1825 u16 version, queue_depth; 1826 int errno; 1827 u8 len; 1828 1829 msg = ev->param.conn.private_data; 1830 len = ev->param.conn.private_data_len; 1831 if (len < sizeof(*msg)) { 1832 rtrs_err(clt, "Invalid RTRS connection response\n"); 1833 return -ECONNRESET; 1834 } 1835 if (le16_to_cpu(msg->magic) != RTRS_MAGIC) { 1836 rtrs_err(clt, "Invalid RTRS magic\n"); 1837 return -ECONNRESET; 1838 } 1839 version = le16_to_cpu(msg->version); 1840 if (version >> 8 != RTRS_PROTO_VER_MAJOR) { 1841 rtrs_err(clt, "Unsupported major RTRS version: %d, expected %d\n", 1842 version >> 8, RTRS_PROTO_VER_MAJOR); 1843 return -ECONNRESET; 1844 } 1845 errno = le16_to_cpu(msg->errno); 1846 if (errno) { 1847 rtrs_err(clt, "Invalid RTRS message: errno %d\n", 1848 errno); 1849 return -ECONNRESET; 1850 } 1851 if (con->c.cid == 0) { 1852 queue_depth = le16_to_cpu(msg->queue_depth); 1853 1854 if (clt_path->queue_depth > 0 && queue_depth != clt_path->queue_depth) { 1855 rtrs_err(clt, "Error: queue depth changed\n"); 1856 1857 /* 1858 * Stop any more reconnection attempts 1859 */ 1860 clt_path->reconnect_attempts = -1; 1861 rtrs_err(clt, 1862 "Disabling auto-reconnect. Trigger a manual reconnect after issue is resolved\n"); 1863 return -ECONNRESET; 1864 } 1865 1866 if (!clt_path->rbufs) { 1867 clt_path->rbufs = kcalloc(queue_depth, 1868 sizeof(*clt_path->rbufs), 1869 GFP_KERNEL); 1870 if (!clt_path->rbufs) 1871 return -ENOMEM; 1872 } 1873 clt_path->queue_depth = queue_depth; 1874 clt_path->s.signal_interval = min_not_zero(queue_depth, 1875 (unsigned short) SERVICE_CON_QUEUE_DEPTH); 1876 clt_path->max_hdr_size = le32_to_cpu(msg->max_hdr_size); 1877 clt_path->max_io_size = le32_to_cpu(msg->max_io_size); 1878 clt_path->flags = le32_to_cpu(msg->flags); 1879 clt_path->chunk_size = clt_path->max_io_size + clt_path->max_hdr_size; 1880 1881 /* 1882 * Global IO size is always a minimum. 1883 * If while a reconnection server sends us a value a bit 1884 * higher - client does not care and uses cached minimum. 1885 * 1886 * Since we can have several sessions (paths) restablishing 1887 * connections in parallel, use lock. 1888 */ 1889 mutex_lock(&clt->paths_mutex); 1890 clt->queue_depth = clt_path->queue_depth; 1891 clt->max_io_size = min_not_zero(clt_path->max_io_size, 1892 clt->max_io_size); 1893 mutex_unlock(&clt->paths_mutex); 1894 1895 /* 1896 * Cache the hca_port and hca_name for sysfs 1897 */ 1898 clt_path->hca_port = con->c.cm_id->port_num; 1899 scnprintf(clt_path->hca_name, sizeof(clt_path->hca_name), 1900 clt_path->s.dev->ib_dev->name); 1901 clt_path->s.src_addr = con->c.cm_id->route.addr.src_addr; 1902 /* set for_new_clt, to allow future reconnect on any path */ 1903 clt_path->for_new_clt = 1; 1904 } 1905 1906 return 0; 1907 } 1908 1909 static inline void flag_success_on_conn(struct rtrs_clt_con *con) 1910 { 1911 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 1912 1913 atomic_inc(&clt_path->connected_cnt); 1914 con->cm_err = 1; 1915 } 1916 1917 static int rtrs_rdma_conn_rejected(struct rtrs_clt_con *con, 1918 struct rdma_cm_event *ev) 1919 { 1920 struct rtrs_path *s = con->c.path; 1921 const struct rtrs_msg_conn_rsp *msg; 1922 const char *rej_msg; 1923 int status, errno; 1924 u8 data_len; 1925 1926 status = ev->status; 1927 rej_msg = rdma_reject_msg(con->c.cm_id, status); 1928 msg = rdma_consumer_reject_data(con->c.cm_id, ev, &data_len); 1929 1930 if (msg && data_len >= sizeof(*msg)) { 1931 errno = (int16_t)le16_to_cpu(msg->errno); 1932 if (errno == -EBUSY) 1933 rtrs_err(s, 1934 "Previous session is still exists on the server, please reconnect later\n"); 1935 else 1936 rtrs_err(s, 1937 "Connect rejected: status %d (%s), rtrs errno %d\n", 1938 status, rej_msg, errno); 1939 } else { 1940 rtrs_err(s, 1941 "Connect rejected but with malformed message: status %d (%s)\n", 1942 status, rej_msg); 1943 } 1944 1945 return -ECONNRESET; 1946 } 1947 1948 void rtrs_clt_close_conns(struct rtrs_clt_path *clt_path, bool wait) 1949 { 1950 if (rtrs_clt_change_state_get_old(clt_path, RTRS_CLT_CLOSING, NULL)) 1951 queue_work(rtrs_wq, &clt_path->close_work); 1952 if (wait) 1953 flush_work(&clt_path->close_work); 1954 } 1955 1956 static inline void flag_error_on_conn(struct rtrs_clt_con *con, int cm_err) 1957 { 1958 if (con->cm_err == 1) { 1959 struct rtrs_clt_path *clt_path; 1960 1961 clt_path = to_clt_path(con->c.path); 1962 if (atomic_dec_and_test(&clt_path->connected_cnt)) 1963 1964 wake_up(&clt_path->state_wq); 1965 } 1966 con->cm_err = cm_err; 1967 } 1968 1969 static int rtrs_clt_rdma_cm_handler(struct rdma_cm_id *cm_id, 1970 struct rdma_cm_event *ev) 1971 { 1972 struct rtrs_clt_con *con = cm_id->context; 1973 struct rtrs_path *s = con->c.path; 1974 struct rtrs_clt_path *clt_path = to_clt_path(s); 1975 int cm_err = 0; 1976 1977 switch (ev->event) { 1978 case RDMA_CM_EVENT_ADDR_RESOLVED: 1979 cm_err = rtrs_rdma_addr_resolved(con); 1980 break; 1981 case RDMA_CM_EVENT_ROUTE_RESOLVED: 1982 cm_err = rtrs_rdma_route_resolved(con); 1983 break; 1984 case RDMA_CM_EVENT_ESTABLISHED: 1985 cm_err = rtrs_rdma_conn_established(con, ev); 1986 if (!cm_err) { 1987 /* 1988 * Report success and wake up. Here we abuse state_wq, 1989 * i.e. wake up without state change, but we set cm_err. 1990 */ 1991 flag_success_on_conn(con); 1992 wake_up(&clt_path->state_wq); 1993 return 0; 1994 } 1995 break; 1996 case RDMA_CM_EVENT_REJECTED: 1997 cm_err = rtrs_rdma_conn_rejected(con, ev); 1998 break; 1999 case RDMA_CM_EVENT_DISCONNECTED: 2000 /* No message for disconnecting */ 2001 cm_err = -ECONNRESET; 2002 break; 2003 case RDMA_CM_EVENT_CONNECT_ERROR: 2004 case RDMA_CM_EVENT_UNREACHABLE: 2005 case RDMA_CM_EVENT_ADDR_CHANGE: 2006 case RDMA_CM_EVENT_TIMEWAIT_EXIT: 2007 rtrs_wrn(s, "CM error (CM event: %s, err: %d)\n", 2008 rdma_event_msg(ev->event), ev->status); 2009 cm_err = -ECONNRESET; 2010 break; 2011 case RDMA_CM_EVENT_ADDR_ERROR: 2012 case RDMA_CM_EVENT_ROUTE_ERROR: 2013 rtrs_wrn(s, "CM error (CM event: %s, err: %d)\n", 2014 rdma_event_msg(ev->event), ev->status); 2015 cm_err = -EHOSTUNREACH; 2016 break; 2017 case RDMA_CM_EVENT_DEVICE_REMOVAL: 2018 /* 2019 * Device removal is a special case. Queue close and return 0. 2020 */ 2021 rtrs_clt_close_conns(clt_path, false); 2022 return 0; 2023 default: 2024 rtrs_err(s, "Unexpected RDMA CM error (CM event: %s, err: %d)\n", 2025 rdma_event_msg(ev->event), ev->status); 2026 cm_err = -ECONNRESET; 2027 break; 2028 } 2029 2030 if (cm_err) { 2031 /* 2032 * cm error makes sense only on connection establishing, 2033 * in other cases we rely on normal procedure of reconnecting. 2034 */ 2035 flag_error_on_conn(con, cm_err); 2036 rtrs_rdma_error_recovery(con); 2037 } 2038 2039 return 0; 2040 } 2041 2042 static int create_cm(struct rtrs_clt_con *con) 2043 { 2044 struct rtrs_path *s = con->c.path; 2045 struct rtrs_clt_path *clt_path = to_clt_path(s); 2046 struct rdma_cm_id *cm_id; 2047 int err; 2048 2049 cm_id = rdma_create_id(&init_net, rtrs_clt_rdma_cm_handler, con, 2050 clt_path->s.dst_addr.ss_family == AF_IB ? 2051 RDMA_PS_IB : RDMA_PS_TCP, IB_QPT_RC); 2052 if (IS_ERR(cm_id)) { 2053 err = PTR_ERR(cm_id); 2054 rtrs_err(s, "Failed to create CM ID, err: %d\n", err); 2055 2056 return err; 2057 } 2058 con->c.cm_id = cm_id; 2059 con->cm_err = 0; 2060 /* allow the port to be reused */ 2061 err = rdma_set_reuseaddr(cm_id, 1); 2062 if (err != 0) { 2063 rtrs_err(s, "Set address reuse failed, err: %d\n", err); 2064 goto destroy_cm; 2065 } 2066 err = rdma_resolve_addr(cm_id, (struct sockaddr *)&clt_path->s.src_addr, 2067 (struct sockaddr *)&clt_path->s.dst_addr, 2068 RTRS_CONNECT_TIMEOUT_MS); 2069 if (err) { 2070 rtrs_err(s, "Failed to resolve address, err: %d\n", err); 2071 goto destroy_cm; 2072 } 2073 /* 2074 * Combine connection status and session events. This is needed 2075 * for waiting two possible cases: cm_err has something meaningful 2076 * or session state was really changed to error by device removal. 2077 */ 2078 err = wait_event_interruptible_timeout( 2079 clt_path->state_wq, 2080 con->cm_err || clt_path->state != RTRS_CLT_CONNECTING, 2081 msecs_to_jiffies(RTRS_CONNECT_TIMEOUT_MS)); 2082 if (err == 0 || err == -ERESTARTSYS) { 2083 if (err == 0) 2084 err = -ETIMEDOUT; 2085 /* Timedout or interrupted */ 2086 goto errr; 2087 } 2088 if (con->cm_err < 0) { 2089 err = con->cm_err; 2090 goto errr; 2091 } 2092 if (READ_ONCE(clt_path->state) != RTRS_CLT_CONNECTING) { 2093 /* Device removal */ 2094 err = -ECONNABORTED; 2095 goto errr; 2096 } 2097 2098 return 0; 2099 2100 errr: 2101 stop_cm(con); 2102 mutex_lock(&con->con_mutex); 2103 destroy_con_cq_qp(con); 2104 mutex_unlock(&con->con_mutex); 2105 destroy_cm: 2106 destroy_cm(con); 2107 2108 return err; 2109 } 2110 2111 static void rtrs_clt_path_up(struct rtrs_clt_path *clt_path) 2112 { 2113 struct rtrs_clt_sess *clt = clt_path->clt; 2114 int up; 2115 2116 /* 2117 * We can fire RECONNECTED event only when all paths were 2118 * connected on rtrs_clt_open(), then each was disconnected 2119 * and the first one connected again. That's why this nasty 2120 * game with counter value. 2121 */ 2122 2123 mutex_lock(&clt->paths_ev_mutex); 2124 up = ++clt->paths_up; 2125 /* 2126 * Here it is safe to access paths num directly since up counter 2127 * is greater than MAX_PATHS_NUM only while rtrs_clt_open() is 2128 * in progress, thus paths removals are impossible. 2129 */ 2130 if (up > MAX_PATHS_NUM && up == MAX_PATHS_NUM + clt->paths_num) 2131 clt->paths_up = clt->paths_num; 2132 else if (up == 1) 2133 clt->link_ev(clt->priv, RTRS_CLT_LINK_EV_RECONNECTED); 2134 mutex_unlock(&clt->paths_ev_mutex); 2135 2136 /* Mark session as established */ 2137 clt_path->established = true; 2138 clt_path->reconnect_attempts = 0; 2139 clt_path->stats->reconnects.successful_cnt++; 2140 } 2141 2142 static void rtrs_clt_path_down(struct rtrs_clt_path *clt_path) 2143 { 2144 struct rtrs_clt_sess *clt = clt_path->clt; 2145 2146 if (!clt_path->established) 2147 return; 2148 2149 clt_path->established = false; 2150 mutex_lock(&clt->paths_ev_mutex); 2151 WARN_ON(!clt->paths_up); 2152 if (--clt->paths_up == 0) 2153 clt->link_ev(clt->priv, RTRS_CLT_LINK_EV_DISCONNECTED); 2154 mutex_unlock(&clt->paths_ev_mutex); 2155 } 2156 2157 static void rtrs_clt_stop_and_destroy_conns(struct rtrs_clt_path *clt_path) 2158 { 2159 struct rtrs_clt_con *con; 2160 unsigned int cid; 2161 2162 WARN_ON(READ_ONCE(clt_path->state) == RTRS_CLT_CONNECTED); 2163 2164 /* 2165 * Possible race with rtrs_clt_open(), when DEVICE_REMOVAL comes 2166 * exactly in between. Start destroying after it finishes. 2167 */ 2168 mutex_lock(&clt_path->init_mutex); 2169 mutex_unlock(&clt_path->init_mutex); 2170 2171 /* 2172 * All IO paths must observe !CONNECTED state before we 2173 * free everything. 2174 */ 2175 synchronize_rcu(); 2176 2177 rtrs_stop_hb(&clt_path->s); 2178 2179 /* 2180 * The order it utterly crucial: firstly disconnect and complete all 2181 * rdma requests with error (thus set in_use=false for requests), 2182 * then fail outstanding requests checking in_use for each, and 2183 * eventually notify upper layer about session disconnection. 2184 */ 2185 2186 for (cid = 0; cid < clt_path->s.con_num; cid++) { 2187 if (!clt_path->s.con[cid]) 2188 break; 2189 con = to_clt_con(clt_path->s.con[cid]); 2190 stop_cm(con); 2191 } 2192 fail_all_outstanding_reqs(clt_path); 2193 free_path_reqs(clt_path); 2194 rtrs_clt_path_down(clt_path); 2195 2196 /* 2197 * Wait for graceful shutdown, namely when peer side invokes 2198 * rdma_disconnect(). 'connected_cnt' is decremented only on 2199 * CM events, thus if other side had crashed and hb has detected 2200 * something is wrong, here we will stuck for exactly timeout ms, 2201 * since CM does not fire anything. That is fine, we are not in 2202 * hurry. 2203 */ 2204 wait_event_timeout(clt_path->state_wq, 2205 !atomic_read(&clt_path->connected_cnt), 2206 msecs_to_jiffies(RTRS_CONNECT_TIMEOUT_MS)); 2207 2208 for (cid = 0; cid < clt_path->s.con_num; cid++) { 2209 if (!clt_path->s.con[cid]) 2210 break; 2211 con = to_clt_con(clt_path->s.con[cid]); 2212 mutex_lock(&con->con_mutex); 2213 destroy_con_cq_qp(con); 2214 mutex_unlock(&con->con_mutex); 2215 destroy_cm(con); 2216 destroy_con(con); 2217 } 2218 } 2219 2220 static inline bool xchg_paths(struct rtrs_clt_path __rcu **rcu_ppcpu_path, 2221 struct rtrs_clt_path *clt_path, 2222 struct rtrs_clt_path *next) 2223 { 2224 struct rtrs_clt_path **ppcpu_path; 2225 2226 /* Call cmpxchg() without sparse warnings */ 2227 ppcpu_path = (typeof(ppcpu_path))rcu_ppcpu_path; 2228 return clt_path == cmpxchg(ppcpu_path, clt_path, next); 2229 } 2230 2231 static void rtrs_clt_remove_path_from_arr(struct rtrs_clt_path *clt_path) 2232 { 2233 struct rtrs_clt_sess *clt = clt_path->clt; 2234 struct rtrs_clt_path *next; 2235 bool wait_for_grace = false; 2236 int cpu; 2237 2238 mutex_lock(&clt->paths_mutex); 2239 list_del_rcu(&clt_path->s.entry); 2240 2241 /* Make sure everybody observes path removal. */ 2242 synchronize_rcu(); 2243 2244 /* 2245 * At this point nobody sees @sess in the list, but still we have 2246 * dangling pointer @pcpu_path which _can_ point to @sess. Since 2247 * nobody can observe @sess in the list, we guarantee that IO path 2248 * will not assign @sess to @pcpu_path, i.e. @pcpu_path can be equal 2249 * to @sess, but can never again become @sess. 2250 */ 2251 2252 /* 2253 * Decrement paths number only after grace period, because 2254 * caller of do_each_path() must firstly observe list without 2255 * path and only then decremented paths number. 2256 * 2257 * Otherwise there can be the following situation: 2258 * o Two paths exist and IO is coming. 2259 * o One path is removed: 2260 * CPU#0 CPU#1 2261 * do_each_path(): rtrs_clt_remove_path_from_arr(): 2262 * path = get_next_path() 2263 * ^^^ list_del_rcu(path) 2264 * [!CONNECTED path] clt->paths_num-- 2265 * ^^^^^^^^^ 2266 * load clt->paths_num from 2 to 1 2267 * ^^^^^^^^^ 2268 * sees 1 2269 * 2270 * path is observed as !CONNECTED, but do_each_path() loop 2271 * ends, because expression i < clt->paths_num is false. 2272 */ 2273 clt->paths_num--; 2274 2275 /* 2276 * Get @next connection from current @sess which is going to be 2277 * removed. If @sess is the last element, then @next is NULL. 2278 */ 2279 rcu_read_lock(); 2280 next = list_next_or_null_rr_rcu(&clt->paths_list, &clt_path->s.entry, 2281 typeof(*next), s.entry); 2282 rcu_read_unlock(); 2283 2284 /* 2285 * @pcpu paths can still point to the path which is going to be 2286 * removed, so change the pointer manually. 2287 */ 2288 for_each_possible_cpu(cpu) { 2289 struct rtrs_clt_path __rcu **ppcpu_path; 2290 2291 ppcpu_path = per_cpu_ptr(clt->pcpu_path, cpu); 2292 if (rcu_dereference_protected(*ppcpu_path, 2293 lockdep_is_held(&clt->paths_mutex)) != clt_path) 2294 /* 2295 * synchronize_rcu() was called just after deleting 2296 * entry from the list, thus IO code path cannot 2297 * change pointer back to the pointer which is going 2298 * to be removed, we are safe here. 2299 */ 2300 continue; 2301 2302 /* 2303 * We race with IO code path, which also changes pointer, 2304 * thus we have to be careful not to overwrite it. 2305 */ 2306 if (xchg_paths(ppcpu_path, clt_path, next)) 2307 /* 2308 * @ppcpu_path was successfully replaced with @next, 2309 * that means that someone could also pick up the 2310 * @sess and dereferencing it right now, so wait for 2311 * a grace period is required. 2312 */ 2313 wait_for_grace = true; 2314 } 2315 if (wait_for_grace) 2316 synchronize_rcu(); 2317 2318 mutex_unlock(&clt->paths_mutex); 2319 } 2320 2321 static void rtrs_clt_add_path_to_arr(struct rtrs_clt_path *clt_path) 2322 { 2323 struct rtrs_clt_sess *clt = clt_path->clt; 2324 2325 mutex_lock(&clt->paths_mutex); 2326 clt->paths_num++; 2327 2328 list_add_tail_rcu(&clt_path->s.entry, &clt->paths_list); 2329 mutex_unlock(&clt->paths_mutex); 2330 } 2331 2332 static void rtrs_clt_close_work(struct work_struct *work) 2333 { 2334 struct rtrs_clt_path *clt_path; 2335 2336 clt_path = container_of(work, struct rtrs_clt_path, close_work); 2337 2338 cancel_work_sync(&clt_path->err_recovery_work); 2339 cancel_delayed_work_sync(&clt_path->reconnect_dwork); 2340 rtrs_clt_stop_and_destroy_conns(clt_path); 2341 rtrs_clt_change_state_get_old(clt_path, RTRS_CLT_CLOSED, NULL); 2342 } 2343 2344 static int init_conns(struct rtrs_clt_path *clt_path) 2345 { 2346 unsigned int cid; 2347 int err; 2348 2349 /* 2350 * On every new session connections increase reconnect counter 2351 * to avoid clashes with previous sessions not yet closed 2352 * sessions on a server side. 2353 */ 2354 clt_path->s.recon_cnt++; 2355 2356 /* Establish all RDMA connections */ 2357 for (cid = 0; cid < clt_path->s.con_num; cid++) { 2358 err = create_con(clt_path, cid); 2359 if (err) 2360 goto destroy; 2361 2362 err = create_cm(to_clt_con(clt_path->s.con[cid])); 2363 if (err) { 2364 destroy_con(to_clt_con(clt_path->s.con[cid])); 2365 goto destroy; 2366 } 2367 } 2368 err = alloc_path_reqs(clt_path); 2369 if (err) 2370 goto destroy; 2371 2372 rtrs_start_hb(&clt_path->s); 2373 2374 return 0; 2375 2376 destroy: 2377 while (cid--) { 2378 struct rtrs_clt_con *con = to_clt_con(clt_path->s.con[cid]); 2379 2380 stop_cm(con); 2381 2382 mutex_lock(&con->con_mutex); 2383 destroy_con_cq_qp(con); 2384 mutex_unlock(&con->con_mutex); 2385 destroy_cm(con); 2386 destroy_con(con); 2387 } 2388 /* 2389 * If we've never taken async path and got an error, say, 2390 * doing rdma_resolve_addr(), switch to CONNECTION_ERR state 2391 * manually to keep reconnecting. 2392 */ 2393 rtrs_clt_change_state_get_old(clt_path, RTRS_CLT_CONNECTING_ERR, NULL); 2394 2395 return err; 2396 } 2397 2398 static void rtrs_clt_info_req_done(struct ib_cq *cq, struct ib_wc *wc) 2399 { 2400 struct rtrs_clt_con *con = to_clt_con(wc->qp->qp_context); 2401 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 2402 struct rtrs_iu *iu; 2403 2404 iu = container_of(wc->wr_cqe, struct rtrs_iu, cqe); 2405 rtrs_iu_free(iu, clt_path->s.dev->ib_dev, 1); 2406 2407 if (wc->status != IB_WC_SUCCESS) { 2408 rtrs_err(clt_path->clt, "Path info request send failed: %s\n", 2409 ib_wc_status_msg(wc->status)); 2410 rtrs_clt_change_state_get_old(clt_path, RTRS_CLT_CONNECTING_ERR, NULL); 2411 return; 2412 } 2413 2414 rtrs_clt_update_wc_stats(con); 2415 } 2416 2417 static int process_info_rsp(struct rtrs_clt_path *clt_path, 2418 const struct rtrs_msg_info_rsp *msg) 2419 { 2420 unsigned int sg_cnt, total_len; 2421 int i, sgi; 2422 2423 sg_cnt = le16_to_cpu(msg->sg_cnt); 2424 if (!sg_cnt || (clt_path->queue_depth % sg_cnt)) { 2425 rtrs_err(clt_path->clt, 2426 "Incorrect sg_cnt %d, is not multiple\n", 2427 sg_cnt); 2428 return -EINVAL; 2429 } 2430 2431 /* 2432 * Check if IB immediate data size is enough to hold the mem_id and 2433 * the offset inside the memory chunk. 2434 */ 2435 if ((ilog2(sg_cnt - 1) + 1) + (ilog2(clt_path->chunk_size - 1) + 1) > 2436 MAX_IMM_PAYL_BITS) { 2437 rtrs_err(clt_path->clt, 2438 "RDMA immediate size (%db) not enough to encode %d buffers of size %dB\n", 2439 MAX_IMM_PAYL_BITS, sg_cnt, clt_path->chunk_size); 2440 return -EINVAL; 2441 } 2442 total_len = 0; 2443 for (sgi = 0, i = 0; sgi < sg_cnt && i < clt_path->queue_depth; sgi++) { 2444 const struct rtrs_sg_desc *desc = &msg->desc[sgi]; 2445 u32 len, rkey; 2446 u64 addr; 2447 2448 addr = le64_to_cpu(desc->addr); 2449 rkey = le32_to_cpu(desc->key); 2450 len = le32_to_cpu(desc->len); 2451 2452 total_len += len; 2453 2454 if (!len || (len % clt_path->chunk_size)) { 2455 rtrs_err(clt_path->clt, "Incorrect [%d].len %d\n", 2456 sgi, 2457 len); 2458 return -EINVAL; 2459 } 2460 for ( ; len && i < clt_path->queue_depth; i++) { 2461 clt_path->rbufs[i].addr = addr; 2462 clt_path->rbufs[i].rkey = rkey; 2463 2464 len -= clt_path->chunk_size; 2465 addr += clt_path->chunk_size; 2466 } 2467 } 2468 /* Sanity check */ 2469 if (sgi != sg_cnt || i != clt_path->queue_depth) { 2470 rtrs_err(clt_path->clt, 2471 "Incorrect sg vector, not fully mapped\n"); 2472 return -EINVAL; 2473 } 2474 if (total_len != clt_path->chunk_size * clt_path->queue_depth) { 2475 rtrs_err(clt_path->clt, "Incorrect total_len %d\n", total_len); 2476 return -EINVAL; 2477 } 2478 2479 return 0; 2480 } 2481 2482 static void rtrs_clt_info_rsp_done(struct ib_cq *cq, struct ib_wc *wc) 2483 { 2484 struct rtrs_clt_con *con = to_clt_con(wc->qp->qp_context); 2485 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 2486 struct rtrs_msg_info_rsp *msg; 2487 enum rtrs_clt_state state; 2488 struct rtrs_iu *iu; 2489 size_t rx_sz; 2490 int err; 2491 2492 state = RTRS_CLT_CONNECTING_ERR; 2493 2494 WARN_ON(con->c.cid); 2495 iu = container_of(wc->wr_cqe, struct rtrs_iu, cqe); 2496 if (wc->status != IB_WC_SUCCESS) { 2497 rtrs_err(clt_path->clt, "Path info response recv failed: %s\n", 2498 ib_wc_status_msg(wc->status)); 2499 goto out; 2500 } 2501 WARN_ON(wc->opcode != IB_WC_RECV); 2502 2503 if (wc->byte_len < sizeof(*msg)) { 2504 rtrs_err(clt_path->clt, "Path info response is malformed: size %d\n", 2505 wc->byte_len); 2506 goto out; 2507 } 2508 ib_dma_sync_single_for_cpu(clt_path->s.dev->ib_dev, iu->dma_addr, 2509 iu->size, DMA_FROM_DEVICE); 2510 msg = iu->buf; 2511 if (le16_to_cpu(msg->type) != RTRS_MSG_INFO_RSP) { 2512 rtrs_err(clt_path->clt, "Path info response is malformed: type %d\n", 2513 le16_to_cpu(msg->type)); 2514 goto out; 2515 } 2516 rx_sz = sizeof(*msg); 2517 rx_sz += sizeof(msg->desc[0]) * le16_to_cpu(msg->sg_cnt); 2518 if (wc->byte_len < rx_sz) { 2519 rtrs_err(clt_path->clt, "Path info response is malformed: size %d\n", 2520 wc->byte_len); 2521 goto out; 2522 } 2523 err = process_info_rsp(clt_path, msg); 2524 if (err) 2525 goto out; 2526 2527 err = post_recv_path(clt_path); 2528 if (err) 2529 goto out; 2530 2531 state = RTRS_CLT_CONNECTED; 2532 2533 out: 2534 rtrs_clt_update_wc_stats(con); 2535 rtrs_iu_free(iu, clt_path->s.dev->ib_dev, 1); 2536 rtrs_clt_change_state_get_old(clt_path, state, NULL); 2537 } 2538 2539 static int rtrs_send_path_info(struct rtrs_clt_path *clt_path) 2540 { 2541 struct rtrs_clt_con *usr_con = to_clt_con(clt_path->s.con[0]); 2542 struct rtrs_msg_info_req *msg; 2543 struct rtrs_iu *tx_iu, *rx_iu; 2544 size_t rx_sz; 2545 int err; 2546 2547 rx_sz = sizeof(struct rtrs_msg_info_rsp); 2548 rx_sz += sizeof(struct rtrs_sg_desc) * clt_path->queue_depth; 2549 2550 tx_iu = rtrs_iu_alloc(1, sizeof(struct rtrs_msg_info_req), GFP_KERNEL, 2551 clt_path->s.dev->ib_dev, DMA_TO_DEVICE, 2552 rtrs_clt_info_req_done); 2553 rx_iu = rtrs_iu_alloc(1, rx_sz, GFP_KERNEL, clt_path->s.dev->ib_dev, 2554 DMA_FROM_DEVICE, rtrs_clt_info_rsp_done); 2555 if (!tx_iu || !rx_iu) { 2556 err = -ENOMEM; 2557 goto out; 2558 } 2559 /* Prepare for getting info response */ 2560 err = rtrs_iu_post_recv(&usr_con->c, rx_iu); 2561 if (err) { 2562 rtrs_err(clt_path->clt, "rtrs_iu_post_recv(), err: %d\n", err); 2563 goto out; 2564 } 2565 rx_iu = NULL; 2566 2567 msg = tx_iu->buf; 2568 msg->type = cpu_to_le16(RTRS_MSG_INFO_REQ); 2569 memcpy(msg->pathname, clt_path->s.sessname, sizeof(msg->pathname)); 2570 2571 ib_dma_sync_single_for_device(clt_path->s.dev->ib_dev, 2572 tx_iu->dma_addr, 2573 tx_iu->size, DMA_TO_DEVICE); 2574 2575 /* Send info request */ 2576 err = rtrs_iu_post_send(&usr_con->c, tx_iu, sizeof(*msg), NULL); 2577 if (err) { 2578 rtrs_err(clt_path->clt, "rtrs_iu_post_send(), err: %d\n", err); 2579 goto out; 2580 } 2581 tx_iu = NULL; 2582 2583 /* Wait for state change */ 2584 wait_event_interruptible_timeout(clt_path->state_wq, 2585 clt_path->state != RTRS_CLT_CONNECTING, 2586 msecs_to_jiffies( 2587 RTRS_CONNECT_TIMEOUT_MS)); 2588 if (READ_ONCE(clt_path->state) != RTRS_CLT_CONNECTED) { 2589 if (READ_ONCE(clt_path->state) == RTRS_CLT_CONNECTING_ERR) 2590 err = -ECONNRESET; 2591 else 2592 err = -ETIMEDOUT; 2593 } 2594 2595 out: 2596 if (tx_iu) 2597 rtrs_iu_free(tx_iu, clt_path->s.dev->ib_dev, 1); 2598 if (rx_iu) 2599 rtrs_iu_free(rx_iu, clt_path->s.dev->ib_dev, 1); 2600 if (err) 2601 /* If we've never taken async path because of malloc problems */ 2602 rtrs_clt_change_state_get_old(clt_path, 2603 RTRS_CLT_CONNECTING_ERR, NULL); 2604 2605 return err; 2606 } 2607 2608 /** 2609 * init_path() - establishes all path connections and does handshake 2610 * @clt_path: client path. 2611 * In case of error full close or reconnect procedure should be taken, 2612 * because reconnect or close async works can be started. 2613 */ 2614 static int init_path(struct rtrs_clt_path *clt_path) 2615 { 2616 int err; 2617 char str[NAME_MAX]; 2618 struct rtrs_addr path = { 2619 .src = &clt_path->s.src_addr, 2620 .dst = &clt_path->s.dst_addr, 2621 }; 2622 2623 rtrs_addr_to_str(&path, str, sizeof(str)); 2624 2625 mutex_lock(&clt_path->init_mutex); 2626 err = init_conns(clt_path); 2627 if (err) { 2628 rtrs_err(clt_path->clt, 2629 "init_conns() failed: err=%d path=%s [%s:%u]\n", err, 2630 str, clt_path->hca_name, clt_path->hca_port); 2631 goto out; 2632 } 2633 err = rtrs_send_path_info(clt_path); 2634 if (err) { 2635 rtrs_err(clt_path->clt, 2636 "rtrs_send_path_info() failed: err=%d path=%s [%s:%u]\n", 2637 err, str, clt_path->hca_name, clt_path->hca_port); 2638 goto out; 2639 } 2640 rtrs_clt_path_up(clt_path); 2641 out: 2642 mutex_unlock(&clt_path->init_mutex); 2643 2644 return err; 2645 } 2646 2647 static void rtrs_clt_reconnect_work(struct work_struct *work) 2648 { 2649 struct rtrs_clt_path *clt_path; 2650 struct rtrs_clt_sess *clt; 2651 int err; 2652 2653 clt_path = container_of(to_delayed_work(work), struct rtrs_clt_path, 2654 reconnect_dwork); 2655 clt = clt_path->clt; 2656 2657 if (READ_ONCE(clt_path->state) != RTRS_CLT_RECONNECTING) 2658 return; 2659 2660 if (clt_path->reconnect_attempts >= clt->max_reconnect_attempts) { 2661 /* Close a path completely if max attempts is reached */ 2662 rtrs_clt_close_conns(clt_path, false); 2663 return; 2664 } 2665 clt_path->reconnect_attempts++; 2666 2667 msleep(RTRS_RECONNECT_BACKOFF); 2668 if (rtrs_clt_change_state_get_old(clt_path, RTRS_CLT_CONNECTING, NULL)) { 2669 err = init_path(clt_path); 2670 if (err) 2671 goto reconnect_again; 2672 } 2673 2674 return; 2675 2676 reconnect_again: 2677 if (rtrs_clt_change_state_get_old(clt_path, RTRS_CLT_RECONNECTING, NULL)) { 2678 clt_path->stats->reconnects.fail_cnt++; 2679 queue_work(rtrs_wq, &clt_path->err_recovery_work); 2680 } 2681 } 2682 2683 static void rtrs_clt_dev_release(struct device *dev) 2684 { 2685 struct rtrs_clt_sess *clt = container_of(dev, struct rtrs_clt_sess, 2686 dev); 2687 2688 mutex_destroy(&clt->paths_ev_mutex); 2689 mutex_destroy(&clt->paths_mutex); 2690 kfree(clt); 2691 } 2692 2693 static struct rtrs_clt_sess *alloc_clt(const char *sessname, size_t paths_num, 2694 u16 port, size_t pdu_sz, void *priv, 2695 void (*link_ev)(void *priv, 2696 enum rtrs_clt_link_ev ev), 2697 unsigned int reconnect_delay_sec, 2698 unsigned int max_reconnect_attempts) 2699 { 2700 struct rtrs_clt_sess *clt; 2701 int err; 2702 2703 if (!paths_num || paths_num > MAX_PATHS_NUM) 2704 return ERR_PTR(-EINVAL); 2705 2706 if (strlen(sessname) >= sizeof(clt->sessname)) 2707 return ERR_PTR(-EINVAL); 2708 2709 clt = kzalloc(sizeof(*clt), GFP_KERNEL); 2710 if (!clt) 2711 return ERR_PTR(-ENOMEM); 2712 2713 clt->pcpu_path = alloc_percpu(typeof(*clt->pcpu_path)); 2714 if (!clt->pcpu_path) { 2715 kfree(clt); 2716 return ERR_PTR(-ENOMEM); 2717 } 2718 2719 clt->dev.class = rtrs_clt_dev_class; 2720 clt->dev.release = rtrs_clt_dev_release; 2721 uuid_gen(&clt->paths_uuid); 2722 INIT_LIST_HEAD_RCU(&clt->paths_list); 2723 clt->paths_num = paths_num; 2724 clt->paths_up = MAX_PATHS_NUM; 2725 clt->port = port; 2726 clt->pdu_sz = pdu_sz; 2727 clt->max_segments = RTRS_MAX_SEGMENTS; 2728 clt->reconnect_delay_sec = reconnect_delay_sec; 2729 clt->max_reconnect_attempts = max_reconnect_attempts; 2730 clt->priv = priv; 2731 clt->link_ev = link_ev; 2732 clt->mp_policy = MP_POLICY_MIN_INFLIGHT; 2733 strscpy(clt->sessname, sessname, sizeof(clt->sessname)); 2734 init_waitqueue_head(&clt->permits_wait); 2735 mutex_init(&clt->paths_ev_mutex); 2736 mutex_init(&clt->paths_mutex); 2737 device_initialize(&clt->dev); 2738 2739 err = dev_set_name(&clt->dev, "%s", sessname); 2740 if (err) 2741 goto err_put; 2742 2743 /* 2744 * Suppress user space notification until 2745 * sysfs files are created 2746 */ 2747 dev_set_uevent_suppress(&clt->dev, true); 2748 err = device_add(&clt->dev); 2749 if (err) 2750 goto err_put; 2751 2752 clt->kobj_paths = kobject_create_and_add("paths", &clt->dev.kobj); 2753 if (!clt->kobj_paths) { 2754 err = -ENOMEM; 2755 goto err_del; 2756 } 2757 err = rtrs_clt_create_sysfs_root_files(clt); 2758 if (err) { 2759 kobject_del(clt->kobj_paths); 2760 kobject_put(clt->kobj_paths); 2761 goto err_del; 2762 } 2763 dev_set_uevent_suppress(&clt->dev, false); 2764 kobject_uevent(&clt->dev.kobj, KOBJ_ADD); 2765 2766 return clt; 2767 err_del: 2768 device_del(&clt->dev); 2769 err_put: 2770 free_percpu(clt->pcpu_path); 2771 put_device(&clt->dev); 2772 return ERR_PTR(err); 2773 } 2774 2775 static void free_clt(struct rtrs_clt_sess *clt) 2776 { 2777 free_percpu(clt->pcpu_path); 2778 2779 /* 2780 * release callback will free clt and destroy mutexes in last put 2781 */ 2782 device_unregister(&clt->dev); 2783 } 2784 2785 /** 2786 * rtrs_clt_open() - Open a path to an RTRS server 2787 * @ops: holds the link event callback and the private pointer. 2788 * @sessname: name of the session 2789 * @paths: Paths to be established defined by their src and dst addresses 2790 * @paths_num: Number of elements in the @paths array 2791 * @port: port to be used by the RTRS session 2792 * @pdu_sz: Size of extra payload which can be accessed after permit allocation. 2793 * @reconnect_delay_sec: time between reconnect tries 2794 * @max_reconnect_attempts: Number of times to reconnect on error before giving 2795 * up, 0 for * disabled, -1 for forever 2796 * @nr_poll_queues: number of polling mode connection using IB_POLL_DIRECT flag 2797 * 2798 * Starts session establishment with the rtrs_server. The function can block 2799 * up to ~2000ms before it returns. 2800 * 2801 * Return a valid pointer on success otherwise PTR_ERR. 2802 */ 2803 struct rtrs_clt_sess *rtrs_clt_open(struct rtrs_clt_ops *ops, 2804 const char *pathname, 2805 const struct rtrs_addr *paths, 2806 size_t paths_num, u16 port, 2807 size_t pdu_sz, u8 reconnect_delay_sec, 2808 s16 max_reconnect_attempts, u32 nr_poll_queues) 2809 { 2810 struct rtrs_clt_path *clt_path, *tmp; 2811 struct rtrs_clt_sess *clt; 2812 int err, i; 2813 2814 if (strchr(pathname, '/') || strchr(pathname, '.')) { 2815 pr_err("pathname cannot contain / and .\n"); 2816 err = -EINVAL; 2817 goto out; 2818 } 2819 2820 clt = alloc_clt(pathname, paths_num, port, pdu_sz, ops->priv, 2821 ops->link_ev, 2822 reconnect_delay_sec, 2823 max_reconnect_attempts); 2824 if (IS_ERR(clt)) { 2825 err = PTR_ERR(clt); 2826 goto out; 2827 } 2828 for (i = 0; i < paths_num; i++) { 2829 struct rtrs_clt_path *clt_path; 2830 2831 clt_path = alloc_path(clt, &paths[i], nr_cpu_ids, 2832 nr_poll_queues); 2833 if (IS_ERR(clt_path)) { 2834 err = PTR_ERR(clt_path); 2835 goto close_all_path; 2836 } 2837 if (!i) 2838 clt_path->for_new_clt = 1; 2839 list_add_tail_rcu(&clt_path->s.entry, &clt->paths_list); 2840 2841 err = init_path(clt_path); 2842 if (err) { 2843 list_del_rcu(&clt_path->s.entry); 2844 rtrs_clt_close_conns(clt_path, true); 2845 free_percpu(clt_path->stats->pcpu_stats); 2846 kfree(clt_path->stats); 2847 free_path(clt_path); 2848 goto close_all_path; 2849 } 2850 2851 err = rtrs_clt_create_path_files(clt_path); 2852 if (err) { 2853 list_del_rcu(&clt_path->s.entry); 2854 rtrs_clt_close_conns(clt_path, true); 2855 free_percpu(clt_path->stats->pcpu_stats); 2856 kfree(clt_path->stats); 2857 free_path(clt_path); 2858 goto close_all_path; 2859 } 2860 } 2861 err = alloc_permits(clt); 2862 if (err) 2863 goto close_all_path; 2864 2865 return clt; 2866 2867 close_all_path: 2868 list_for_each_entry_safe(clt_path, tmp, &clt->paths_list, s.entry) { 2869 rtrs_clt_destroy_path_files(clt_path, NULL); 2870 rtrs_clt_close_conns(clt_path, true); 2871 kobject_put(&clt_path->kobj); 2872 } 2873 rtrs_clt_destroy_sysfs_root(clt); 2874 free_clt(clt); 2875 2876 out: 2877 return ERR_PTR(err); 2878 } 2879 EXPORT_SYMBOL(rtrs_clt_open); 2880 2881 /** 2882 * rtrs_clt_close() - Close a path 2883 * @clt: Session handle. Session is freed upon return. 2884 */ 2885 void rtrs_clt_close(struct rtrs_clt_sess *clt) 2886 { 2887 struct rtrs_clt_path *clt_path, *tmp; 2888 2889 /* Firstly forbid sysfs access */ 2890 rtrs_clt_destroy_sysfs_root(clt); 2891 2892 /* Now it is safe to iterate over all paths without locks */ 2893 list_for_each_entry_safe(clt_path, tmp, &clt->paths_list, s.entry) { 2894 rtrs_clt_close_conns(clt_path, true); 2895 rtrs_clt_destroy_path_files(clt_path, NULL); 2896 kobject_put(&clt_path->kobj); 2897 } 2898 free_permits(clt); 2899 free_clt(clt); 2900 } 2901 EXPORT_SYMBOL(rtrs_clt_close); 2902 2903 int rtrs_clt_reconnect_from_sysfs(struct rtrs_clt_path *clt_path) 2904 { 2905 enum rtrs_clt_state old_state; 2906 int err = -EBUSY; 2907 bool changed; 2908 2909 changed = rtrs_clt_change_state_get_old(clt_path, 2910 RTRS_CLT_RECONNECTING, 2911 &old_state); 2912 if (changed) { 2913 clt_path->reconnect_attempts = 0; 2914 rtrs_clt_stop_and_destroy_conns(clt_path); 2915 queue_delayed_work(rtrs_wq, &clt_path->reconnect_dwork, 0); 2916 } 2917 if (changed || old_state == RTRS_CLT_RECONNECTING) { 2918 /* 2919 * flush_delayed_work() queues pending work for immediate 2920 * execution, so do the flush if we have queued something 2921 * right now or work is pending. 2922 */ 2923 flush_delayed_work(&clt_path->reconnect_dwork); 2924 err = (READ_ONCE(clt_path->state) == 2925 RTRS_CLT_CONNECTED ? 0 : -ENOTCONN); 2926 } 2927 2928 return err; 2929 } 2930 2931 int rtrs_clt_remove_path_from_sysfs(struct rtrs_clt_path *clt_path, 2932 const struct attribute *sysfs_self) 2933 { 2934 enum rtrs_clt_state old_state; 2935 bool changed; 2936 2937 /* 2938 * Continue stopping path till state was changed to DEAD or 2939 * state was observed as DEAD: 2940 * 1. State was changed to DEAD - we were fast and nobody 2941 * invoked rtrs_clt_reconnect(), which can again start 2942 * reconnecting. 2943 * 2. State was observed as DEAD - we have someone in parallel 2944 * removing the path. 2945 */ 2946 do { 2947 rtrs_clt_close_conns(clt_path, true); 2948 changed = rtrs_clt_change_state_get_old(clt_path, 2949 RTRS_CLT_DEAD, 2950 &old_state); 2951 } while (!changed && old_state != RTRS_CLT_DEAD); 2952 2953 if (changed) { 2954 rtrs_clt_remove_path_from_arr(clt_path); 2955 rtrs_clt_destroy_path_files(clt_path, sysfs_self); 2956 kobject_put(&clt_path->kobj); 2957 } 2958 2959 return 0; 2960 } 2961 2962 void rtrs_clt_set_max_reconnect_attempts(struct rtrs_clt_sess *clt, int value) 2963 { 2964 clt->max_reconnect_attempts = (unsigned int)value; 2965 } 2966 2967 int rtrs_clt_get_max_reconnect_attempts(const struct rtrs_clt_sess *clt) 2968 { 2969 return (int)clt->max_reconnect_attempts; 2970 } 2971 2972 /** 2973 * rtrs_clt_request() - Request data transfer to/from server via RDMA. 2974 * 2975 * @dir: READ/WRITE 2976 * @ops: callback function to be called as confirmation, and the pointer. 2977 * @clt: Session 2978 * @permit: Preallocated permit 2979 * @vec: Message that is sent to server together with the request. 2980 * Sum of len of all @vec elements limited to <= IO_MSG_SIZE. 2981 * Since the msg is copied internally it can be allocated on stack. 2982 * @nr: Number of elements in @vec. 2983 * @data_len: length of data sent to/from server 2984 * @sg: Pages to be sent/received to/from server. 2985 * @sg_cnt: Number of elements in the @sg 2986 * 2987 * Return: 2988 * 0: Success 2989 * <0: Error 2990 * 2991 * On dir=READ rtrs client will request a data transfer from Server to client. 2992 * The data that the server will respond with will be stored in @sg when 2993 * the user receives an %RTRS_CLT_RDMA_EV_RDMA_REQUEST_WRITE_COMPL event. 2994 * On dir=WRITE rtrs client will rdma write data in sg to server side. 2995 */ 2996 int rtrs_clt_request(int dir, struct rtrs_clt_req_ops *ops, 2997 struct rtrs_clt_sess *clt, struct rtrs_permit *permit, 2998 const struct kvec *vec, size_t nr, size_t data_len, 2999 struct scatterlist *sg, unsigned int sg_cnt) 3000 { 3001 struct rtrs_clt_io_req *req; 3002 struct rtrs_clt_path *clt_path; 3003 3004 enum dma_data_direction dma_dir; 3005 int err = -ECONNABORTED, i; 3006 size_t usr_len, hdr_len; 3007 struct path_it it; 3008 3009 /* Get kvec length */ 3010 for (i = 0, usr_len = 0; i < nr; i++) 3011 usr_len += vec[i].iov_len; 3012 3013 if (dir == READ) { 3014 hdr_len = sizeof(struct rtrs_msg_rdma_read) + 3015 sg_cnt * sizeof(struct rtrs_sg_desc); 3016 dma_dir = DMA_FROM_DEVICE; 3017 } else { 3018 hdr_len = sizeof(struct rtrs_msg_rdma_write); 3019 dma_dir = DMA_TO_DEVICE; 3020 } 3021 3022 rcu_read_lock(); 3023 for (path_it_init(&it, clt); 3024 (clt_path = it.next_path(&it)) && it.i < it.clt->paths_num; it.i++) { 3025 if (READ_ONCE(clt_path->state) != RTRS_CLT_CONNECTED) 3026 continue; 3027 3028 if (usr_len + hdr_len > clt_path->max_hdr_size) { 3029 rtrs_wrn_rl(clt_path->clt, 3030 "%s request failed, user message size is %zu and header length %zu, but max size is %u\n", 3031 dir == READ ? "Read" : "Write", 3032 usr_len, hdr_len, clt_path->max_hdr_size); 3033 err = -EMSGSIZE; 3034 break; 3035 } 3036 req = rtrs_clt_get_req(clt_path, ops->conf_fn, permit, ops->priv, 3037 vec, usr_len, sg, sg_cnt, data_len, 3038 dma_dir); 3039 if (dir == READ) 3040 err = rtrs_clt_read_req(req); 3041 else 3042 err = rtrs_clt_write_req(req); 3043 if (err) { 3044 req->in_use = false; 3045 continue; 3046 } 3047 /* Success path */ 3048 break; 3049 } 3050 path_it_deinit(&it); 3051 rcu_read_unlock(); 3052 3053 return err; 3054 } 3055 EXPORT_SYMBOL(rtrs_clt_request); 3056 3057 int rtrs_clt_rdma_cq_direct(struct rtrs_clt_sess *clt, unsigned int index) 3058 { 3059 /* If no path, return -1 for block layer not to try again */ 3060 int cnt = -1; 3061 struct rtrs_con *con; 3062 struct rtrs_clt_path *clt_path; 3063 struct path_it it; 3064 3065 rcu_read_lock(); 3066 for (path_it_init(&it, clt); 3067 (clt_path = it.next_path(&it)) && it.i < it.clt->paths_num; it.i++) { 3068 if (READ_ONCE(clt_path->state) != RTRS_CLT_CONNECTED) 3069 continue; 3070 3071 con = clt_path->s.con[index + 1]; 3072 cnt = ib_process_cq_direct(con->cq, -1); 3073 if (cnt) 3074 break; 3075 } 3076 path_it_deinit(&it); 3077 rcu_read_unlock(); 3078 3079 return cnt; 3080 } 3081 EXPORT_SYMBOL(rtrs_clt_rdma_cq_direct); 3082 3083 /** 3084 * rtrs_clt_query() - queries RTRS session attributes 3085 *@clt: session pointer 3086 *@attr: query results for session attributes. 3087 * Returns: 3088 * 0 on success 3089 * -ECOMM no connection to the server 3090 */ 3091 int rtrs_clt_query(struct rtrs_clt_sess *clt, struct rtrs_attrs *attr) 3092 { 3093 if (!rtrs_clt_is_connected(clt)) 3094 return -ECOMM; 3095 3096 attr->queue_depth = clt->queue_depth; 3097 attr->max_segments = clt->max_segments; 3098 /* Cap max_io_size to min of remote buffer size and the fr pages */ 3099 attr->max_io_size = min_t(int, clt->max_io_size, 3100 clt->max_segments * SZ_4K); 3101 3102 return 0; 3103 } 3104 EXPORT_SYMBOL(rtrs_clt_query); 3105 3106 int rtrs_clt_create_path_from_sysfs(struct rtrs_clt_sess *clt, 3107 struct rtrs_addr *addr) 3108 { 3109 struct rtrs_clt_path *clt_path; 3110 int err; 3111 3112 clt_path = alloc_path(clt, addr, nr_cpu_ids, 0); 3113 if (IS_ERR(clt_path)) 3114 return PTR_ERR(clt_path); 3115 3116 mutex_lock(&clt->paths_mutex); 3117 if (clt->paths_num == 0) { 3118 /* 3119 * When all the paths are removed for a session, 3120 * the addition of the first path is like a new session for 3121 * the storage server 3122 */ 3123 clt_path->for_new_clt = 1; 3124 } 3125 3126 mutex_unlock(&clt->paths_mutex); 3127 3128 /* 3129 * It is totally safe to add path in CONNECTING state: coming 3130 * IO will never grab it. Also it is very important to add 3131 * path before init, since init fires LINK_CONNECTED event. 3132 */ 3133 rtrs_clt_add_path_to_arr(clt_path); 3134 3135 err = init_path(clt_path); 3136 if (err) 3137 goto close_path; 3138 3139 err = rtrs_clt_create_path_files(clt_path); 3140 if (err) 3141 goto close_path; 3142 3143 return 0; 3144 3145 close_path: 3146 rtrs_clt_remove_path_from_arr(clt_path); 3147 rtrs_clt_close_conns(clt_path, true); 3148 free_percpu(clt_path->stats->pcpu_stats); 3149 kfree(clt_path->stats); 3150 free_path(clt_path); 3151 3152 return err; 3153 } 3154 3155 static int rtrs_clt_ib_dev_init(struct rtrs_ib_dev *dev) 3156 { 3157 if (!(dev->ib_dev->attrs.device_cap_flags & 3158 IB_DEVICE_MEM_MGT_EXTENSIONS)) { 3159 pr_err("Memory registrations not supported.\n"); 3160 return -ENOTSUPP; 3161 } 3162 3163 return 0; 3164 } 3165 3166 static const struct rtrs_rdma_dev_pd_ops dev_pd_ops = { 3167 .init = rtrs_clt_ib_dev_init 3168 }; 3169 3170 static int __init rtrs_client_init(void) 3171 { 3172 rtrs_rdma_dev_pd_init(0, &dev_pd); 3173 3174 rtrs_clt_dev_class = class_create(THIS_MODULE, "rtrs-client"); 3175 if (IS_ERR(rtrs_clt_dev_class)) { 3176 pr_err("Failed to create rtrs-client dev class\n"); 3177 return PTR_ERR(rtrs_clt_dev_class); 3178 } 3179 rtrs_wq = alloc_workqueue("rtrs_client_wq", 0, 0); 3180 if (!rtrs_wq) { 3181 class_destroy(rtrs_clt_dev_class); 3182 return -ENOMEM; 3183 } 3184 3185 return 0; 3186 } 3187 3188 static void __exit rtrs_client_exit(void) 3189 { 3190 destroy_workqueue(rtrs_wq); 3191 class_destroy(rtrs_clt_dev_class); 3192 rtrs_rdma_dev_pd_deinit(&dev_pd); 3193 } 3194 3195 module_init(rtrs_client_init); 3196 module_exit(rtrs_client_exit); 3197