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 #include "rtrs-clt-trace.h" 20 21 #define RTRS_CONNECT_TIMEOUT_MS 30000 22 /* 23 * Wait a bit before trying to reconnect after a failure 24 * in order to give server time to finish clean up which 25 * leads to "false positives" failed reconnect attempts 26 */ 27 #define RTRS_RECONNECT_BACKOFF 1000 28 /* 29 * Wait for additional random time between 0 and 8 seconds 30 * before starting to reconnect to avoid clients reconnecting 31 * all at once in case of a major network outage 32 */ 33 #define RTRS_RECONNECT_SEED 8 34 35 #define FIRST_CONN 0x01 36 /* limit to 128 * 4k = 512k max IO */ 37 #define RTRS_MAX_SEGMENTS 128 38 39 MODULE_DESCRIPTION("RDMA Transport Client"); 40 MODULE_LICENSE("GPL"); 41 42 static const struct rtrs_rdma_dev_pd_ops dev_pd_ops; 43 static struct rtrs_rdma_dev_pd dev_pd = { 44 .ops = &dev_pd_ops 45 }; 46 47 static struct workqueue_struct *rtrs_wq; 48 static const struct class rtrs_clt_dev_class = { 49 .name = "rtrs-client", 50 }; 51 52 static inline bool rtrs_clt_is_connected(const struct rtrs_clt_sess *clt) 53 { 54 struct rtrs_clt_path *clt_path; 55 bool connected = false; 56 57 rcu_read_lock(); 58 list_for_each_entry_rcu(clt_path, &clt->paths_list, s.entry) 59 if (READ_ONCE(clt_path->state) == RTRS_CLT_CONNECTED) { 60 connected = true; 61 break; 62 } 63 rcu_read_unlock(); 64 65 return connected; 66 } 67 68 static struct rtrs_permit * 69 __rtrs_get_permit(struct rtrs_clt_sess *clt, enum rtrs_clt_con_type con_type) 70 { 71 size_t max_depth = clt->queue_depth; 72 struct rtrs_permit *permit; 73 int bit; 74 75 /* 76 * Adapted from null_blk get_tag(). Callers from different cpus may 77 * grab the same bit, since find_first_zero_bit is not atomic. 78 * But then the test_and_set_bit_lock will fail for all the 79 * callers but one, so that they will loop again. 80 * This way an explicit spinlock is not required. 81 */ 82 do { 83 bit = find_first_zero_bit(clt->permits_map, max_depth); 84 if (bit >= max_depth) 85 return NULL; 86 } while (test_and_set_bit_lock(bit, clt->permits_map)); 87 88 permit = get_permit(clt, bit); 89 WARN_ON(permit->mem_id != bit); 90 permit->cpu_id = raw_smp_processor_id(); 91 permit->con_type = con_type; 92 93 return permit; 94 } 95 96 static inline void __rtrs_put_permit(struct rtrs_clt_sess *clt, 97 struct rtrs_permit *permit) 98 { 99 clear_bit_unlock(permit->mem_id, clt->permits_map); 100 } 101 102 /** 103 * rtrs_clt_get_permit() - allocates permit for future RDMA operation 104 * @clt: Current session 105 * @con_type: Type of connection to use with the permit 106 * @can_wait: Wait type 107 * 108 * Description: 109 * Allocates permit for the following RDMA operation. Permit is used 110 * to preallocate all resources and to propagate memory pressure 111 * up earlier. 112 * 113 * Context: 114 * Can sleep if @wait == RTRS_PERMIT_WAIT 115 */ 116 struct rtrs_permit *rtrs_clt_get_permit(struct rtrs_clt_sess *clt, 117 enum rtrs_clt_con_type con_type, 118 enum wait_type can_wait) 119 { 120 struct rtrs_permit *permit; 121 DEFINE_WAIT(wait); 122 123 permit = __rtrs_get_permit(clt, con_type); 124 if (permit || !can_wait) 125 return permit; 126 127 do { 128 prepare_to_wait(&clt->permits_wait, &wait, 129 TASK_UNINTERRUPTIBLE); 130 permit = __rtrs_get_permit(clt, con_type); 131 if (permit) 132 break; 133 134 io_schedule(); 135 } while (1); 136 137 finish_wait(&clt->permits_wait, &wait); 138 139 return permit; 140 } 141 EXPORT_SYMBOL(rtrs_clt_get_permit); 142 143 /** 144 * rtrs_clt_put_permit() - puts allocated permit 145 * @clt: Current session 146 * @permit: Permit to be freed 147 * 148 * Context: 149 * Does not matter 150 */ 151 void rtrs_clt_put_permit(struct rtrs_clt_sess *clt, 152 struct rtrs_permit *permit) 153 { 154 if (WARN_ON(!test_bit(permit->mem_id, clt->permits_map))) 155 return; 156 157 __rtrs_put_permit(clt, permit); 158 159 /* 160 * rtrs_clt_get_permit() adds itself to the &clt->permits_wait list 161 * before calling schedule(). So if rtrs_clt_get_permit() is sleeping 162 * it must have added itself to &clt->permits_wait before 163 * __rtrs_put_permit() finished. 164 * Hence it is safe to guard wake_up() with a waitqueue_active() test. 165 */ 166 if (waitqueue_active(&clt->permits_wait)) 167 wake_up(&clt->permits_wait); 168 } 169 EXPORT_SYMBOL(rtrs_clt_put_permit); 170 171 /** 172 * rtrs_permit_to_clt_con() - returns RDMA connection pointer by the permit 173 * @clt_path: client path pointer 174 * @permit: permit for the allocation of the RDMA buffer 175 * Note: 176 * IO connection starts from 1. 177 * 0 connection is for user messages. 178 */ 179 static 180 struct rtrs_clt_con *rtrs_permit_to_clt_con(struct rtrs_clt_path *clt_path, 181 struct rtrs_permit *permit) 182 { 183 int id = 0; 184 185 if (permit->con_type == RTRS_IO_CON) 186 id = (permit->cpu_id % (clt_path->s.irq_con_num - 1)) + 1; 187 188 return to_clt_con(clt_path->s.con[id]); 189 } 190 191 /** 192 * rtrs_clt_change_state() - change the session state through session state 193 * machine. 194 * 195 * @clt_path: client path to change the state of. 196 * @new_state: state to change to. 197 * 198 * returns true if sess's state is changed to new state, otherwise return false. 199 * 200 * Locks: 201 * state_wq lock must be hold. 202 */ 203 static bool rtrs_clt_change_state(struct rtrs_clt_path *clt_path, 204 enum rtrs_clt_state new_state) 205 { 206 enum rtrs_clt_state old_state; 207 bool changed = false; 208 209 lockdep_assert_held(&clt_path->state_wq.lock); 210 211 old_state = clt_path->state; 212 switch (new_state) { 213 case RTRS_CLT_CONNECTING: 214 switch (old_state) { 215 case RTRS_CLT_RECONNECTING: 216 changed = true; 217 fallthrough; 218 default: 219 break; 220 } 221 break; 222 case RTRS_CLT_RECONNECTING: 223 switch (old_state) { 224 case RTRS_CLT_CONNECTED: 225 case RTRS_CLT_CONNECTING_ERR: 226 case RTRS_CLT_CLOSED: 227 changed = true; 228 fallthrough; 229 default: 230 break; 231 } 232 break; 233 case RTRS_CLT_CONNECTED: 234 switch (old_state) { 235 case RTRS_CLT_CONNECTING: 236 changed = true; 237 fallthrough; 238 default: 239 break; 240 } 241 break; 242 case RTRS_CLT_CONNECTING_ERR: 243 switch (old_state) { 244 case RTRS_CLT_CONNECTING: 245 changed = true; 246 fallthrough; 247 default: 248 break; 249 } 250 break; 251 case RTRS_CLT_CLOSING: 252 switch (old_state) { 253 case RTRS_CLT_CONNECTING: 254 case RTRS_CLT_CONNECTING_ERR: 255 case RTRS_CLT_RECONNECTING: 256 case RTRS_CLT_CONNECTED: 257 changed = true; 258 fallthrough; 259 default: 260 break; 261 } 262 break; 263 case RTRS_CLT_CLOSED: 264 switch (old_state) { 265 case RTRS_CLT_CLOSING: 266 changed = true; 267 fallthrough; 268 default: 269 break; 270 } 271 break; 272 case RTRS_CLT_DEAD: 273 switch (old_state) { 274 case RTRS_CLT_CLOSED: 275 changed = true; 276 fallthrough; 277 default: 278 break; 279 } 280 break; 281 default: 282 break; 283 } 284 if (changed) { 285 clt_path->state = new_state; 286 wake_up_locked(&clt_path->state_wq); 287 } 288 289 return changed; 290 } 291 292 static bool rtrs_clt_change_state_from_to(struct rtrs_clt_path *clt_path, 293 enum rtrs_clt_state old_state, 294 enum rtrs_clt_state new_state) 295 { 296 bool changed = false; 297 298 spin_lock_irq(&clt_path->state_wq.lock); 299 if (clt_path->state == old_state) 300 changed = rtrs_clt_change_state(clt_path, new_state); 301 spin_unlock_irq(&clt_path->state_wq.lock); 302 303 return changed; 304 } 305 306 static void rtrs_clt_stop_and_destroy_conns(struct rtrs_clt_path *clt_path); 307 static void rtrs_rdma_error_recovery(struct rtrs_clt_con *con) 308 { 309 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 310 311 trace_rtrs_rdma_error_recovery(clt_path); 312 313 if (rtrs_clt_change_state_from_to(clt_path, 314 RTRS_CLT_CONNECTED, 315 RTRS_CLT_RECONNECTING)) { 316 queue_work(rtrs_wq, &clt_path->err_recovery_work); 317 } else { 318 /* 319 * Error can happen just on establishing new connection, 320 * so notify waiter with error state, waiter is responsible 321 * for cleaning the rest and reconnect if needed. 322 */ 323 rtrs_clt_change_state_from_to(clt_path, 324 RTRS_CLT_CONNECTING, 325 RTRS_CLT_CONNECTING_ERR); 326 } 327 } 328 329 static void rtrs_clt_fast_reg_done(struct ib_cq *cq, struct ib_wc *wc) 330 { 331 struct rtrs_clt_con *con = to_clt_con(wc->qp->qp_context); 332 333 if (wc->status != IB_WC_SUCCESS) { 334 rtrs_err_rl(con->c.path, "Failed IB_WR_REG_MR: %s\n", 335 ib_wc_status_msg(wc->status)); 336 rtrs_rdma_error_recovery(con); 337 } 338 } 339 340 static struct ib_cqe fast_reg_cqe = { 341 .done = rtrs_clt_fast_reg_done 342 }; 343 344 static void complete_rdma_req(struct rtrs_clt_io_req *req, int errno, 345 bool notify, bool can_wait); 346 347 static void rtrs_clt_inv_rkey_done(struct ib_cq *cq, struct ib_wc *wc) 348 { 349 struct rtrs_clt_io_req *req = 350 container_of(wc->wr_cqe, typeof(*req), inv_cqe); 351 struct rtrs_clt_con *con = to_clt_con(wc->qp->qp_context); 352 353 if (wc->status != IB_WC_SUCCESS) { 354 rtrs_err_rl(con->c.path, "Failed IB_WR_LOCAL_INV: %s\n", 355 ib_wc_status_msg(wc->status)); 356 rtrs_rdma_error_recovery(con); 357 } 358 req->mr->need_inval = false; 359 if (req->need_inv_comp) 360 complete(&req->inv_comp); 361 else 362 /* Complete request from INV callback */ 363 complete_rdma_req(req, req->inv_errno, true, false); 364 } 365 366 static int rtrs_inv_rkey(struct rtrs_clt_io_req *req) 367 { 368 struct rtrs_clt_con *con = req->con; 369 struct ib_send_wr wr = { 370 .opcode = IB_WR_LOCAL_INV, 371 .wr_cqe = &req->inv_cqe, 372 .send_flags = IB_SEND_SIGNALED, 373 .ex.invalidate_rkey = req->mr->rkey, 374 }; 375 req->inv_cqe.done = rtrs_clt_inv_rkey_done; 376 377 return ib_post_send(con->c.qp, &wr, NULL); 378 } 379 380 static void complete_rdma_req(struct rtrs_clt_io_req *req, int errno, 381 bool notify, bool can_wait) 382 { 383 struct rtrs_clt_con *con = req->con; 384 struct rtrs_clt_path *clt_path; 385 int err; 386 387 if (!req->in_use) 388 return; 389 if (WARN_ON(!req->con)) 390 return; 391 clt_path = to_clt_path(con->c.path); 392 393 if (req->sg_cnt) { 394 if (req->mr->need_inval) { 395 /* 396 * We are here to invalidate read/write requests 397 * ourselves. In normal scenario server should 398 * send INV for all read requests, we do local 399 * invalidate for write requests ourselves, but 400 * we are here, thus three things could happen: 401 * 402 * 1. this is failover, when errno != 0 403 * and can_wait == 1, 404 * 405 * 2. something totally bad happened and 406 * server forgot to send INV, so we 407 * should do that ourselves. 408 * 409 * 3. write request finishes, we need to do local 410 * invalidate 411 */ 412 413 if (can_wait) { 414 req->need_inv_comp = true; 415 } else { 416 /* This should be IO path, so always notify */ 417 WARN_ON(!notify); 418 /* Save errno for INV callback */ 419 req->inv_errno = errno; 420 } 421 422 refcount_inc(&req->ref); 423 err = rtrs_inv_rkey(req); 424 if (err) { 425 rtrs_err_rl(con->c.path, "Send INV WR key=%#x: %d\n", 426 req->mr->rkey, err); 427 } else if (can_wait) { 428 wait_for_completion(&req->inv_comp); 429 } 430 if (!refcount_dec_and_test(&req->ref)) 431 return; 432 } 433 ib_dma_unmap_sg(clt_path->s.dev->ib_dev, req->sglist, 434 req->sg_cnt, req->dir); 435 } 436 if (!refcount_dec_and_test(&req->ref)) 437 return; 438 if (req->mp_policy == MP_POLICY_MIN_INFLIGHT) 439 atomic_dec(&clt_path->stats->inflight); 440 441 req->in_use = false; 442 req->con = NULL; 443 444 if (errno) { 445 rtrs_err_rl(con->c.path, 446 "IO %s request failed: error=%d path=%s [%s:%u] notify=%d\n", 447 req->dir == DMA_TO_DEVICE ? "write" : "read", errno, 448 kobject_name(&clt_path->kobj), clt_path->hca_name, 449 clt_path->hca_port, notify); 450 } 451 452 if (notify) 453 req->conf(req->priv, errno); 454 } 455 456 static int rtrs_post_send_rdma(struct rtrs_clt_con *con, 457 struct rtrs_clt_io_req *req, 458 struct rtrs_rbuf *rbuf, u32 off, 459 u32 imm, struct ib_send_wr *wr) 460 { 461 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 462 enum ib_send_flags flags; 463 struct ib_sge sge; 464 465 if (!req->sg_size) { 466 rtrs_wrn(con->c.path, 467 "Doing RDMA Write failed, no data supplied\n"); 468 return -EINVAL; 469 } 470 471 /* user data and user message in the first list element */ 472 sge.addr = req->iu->dma_addr; 473 sge.length = req->sg_size; 474 sge.lkey = clt_path->s.dev->ib_pd->local_dma_lkey; 475 476 /* 477 * From time to time we have to post signalled sends, 478 * or send queue will fill up and only QP reset can help. 479 */ 480 flags = atomic_inc_return(&con->c.wr_cnt) % clt_path->s.signal_interval ? 481 0 : IB_SEND_SIGNALED; 482 483 ib_dma_sync_single_for_device(clt_path->s.dev->ib_dev, 484 req->iu->dma_addr, 485 req->sg_size, DMA_TO_DEVICE); 486 487 return rtrs_iu_post_rdma_write_imm(&con->c, req->iu, &sge, 1, 488 rbuf->rkey, rbuf->addr + off, 489 imm, flags, wr, NULL); 490 } 491 492 static void process_io_rsp(struct rtrs_clt_path *clt_path, u32 msg_id, 493 s16 errno, bool w_inval) 494 { 495 struct rtrs_clt_io_req *req; 496 497 if (WARN_ON(msg_id >= clt_path->queue_depth)) 498 return; 499 500 req = &clt_path->reqs[msg_id]; 501 /* Drop need_inv if server responded with send with invalidation */ 502 req->mr->need_inval &= !w_inval; 503 complete_rdma_req(req, errno, true, false); 504 } 505 506 static void rtrs_clt_recv_done(struct rtrs_clt_con *con, struct ib_wc *wc) 507 { 508 struct rtrs_iu *iu; 509 int err; 510 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 511 512 WARN_ON((clt_path->flags & RTRS_MSG_NEW_RKEY_F) == 0); 513 iu = container_of(wc->wr_cqe, struct rtrs_iu, 514 cqe); 515 err = rtrs_iu_post_recv(&con->c, iu); 516 if (err) { 517 rtrs_err(con->c.path, "post iu failed %d\n", err); 518 rtrs_rdma_error_recovery(con); 519 } 520 } 521 522 static void rtrs_clt_rkey_rsp_done(struct rtrs_clt_con *con, struct ib_wc *wc) 523 { 524 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 525 struct rtrs_msg_rkey_rsp *msg; 526 u32 imm_type, imm_payload; 527 bool w_inval = false; 528 struct rtrs_iu *iu; 529 u32 buf_id; 530 int err; 531 532 WARN_ON((clt_path->flags & RTRS_MSG_NEW_RKEY_F) == 0); 533 534 iu = container_of(wc->wr_cqe, struct rtrs_iu, cqe); 535 536 if (wc->byte_len < sizeof(*msg)) { 537 rtrs_err(con->c.path, "rkey response is malformed: size %d\n", 538 wc->byte_len); 539 goto out; 540 } 541 ib_dma_sync_single_for_cpu(clt_path->s.dev->ib_dev, iu->dma_addr, 542 iu->size, DMA_FROM_DEVICE); 543 msg = iu->buf; 544 if (le16_to_cpu(msg->type) != RTRS_MSG_RKEY_RSP) { 545 rtrs_err(clt_path->clt, 546 "rkey response is malformed: type %d\n", 547 le16_to_cpu(msg->type)); 548 goto out; 549 } 550 buf_id = le16_to_cpu(msg->buf_id); 551 if (WARN_ON(buf_id >= clt_path->queue_depth)) 552 goto out; 553 554 rtrs_from_imm(be32_to_cpu(wc->ex.imm_data), &imm_type, &imm_payload); 555 if (imm_type == RTRS_IO_RSP_IMM || 556 imm_type == RTRS_IO_RSP_W_INV_IMM) { 557 u32 msg_id; 558 559 w_inval = (imm_type == RTRS_IO_RSP_W_INV_IMM); 560 rtrs_from_io_rsp_imm(imm_payload, &msg_id, &err); 561 562 if (WARN_ON(buf_id != msg_id)) 563 goto out; 564 clt_path->rbufs[buf_id].rkey = le32_to_cpu(msg->rkey); 565 process_io_rsp(clt_path, msg_id, err, w_inval); 566 } 567 ib_dma_sync_single_for_device(clt_path->s.dev->ib_dev, iu->dma_addr, 568 iu->size, DMA_FROM_DEVICE); 569 return rtrs_clt_recv_done(con, wc); 570 out: 571 rtrs_rdma_error_recovery(con); 572 } 573 574 static void rtrs_clt_rdma_done(struct ib_cq *cq, struct ib_wc *wc); 575 576 static struct ib_cqe io_comp_cqe = { 577 .done = rtrs_clt_rdma_done 578 }; 579 580 /* 581 * Post x2 empty WRs: first is for this RDMA with IMM, 582 * second is for RECV with INV, which happened earlier. 583 */ 584 static int rtrs_post_recv_empty_x2(struct rtrs_con *con, struct ib_cqe *cqe) 585 { 586 struct ib_recv_wr wr_arr[2], *wr; 587 int i; 588 589 memset(wr_arr, 0, sizeof(wr_arr)); 590 for (i = 0; i < ARRAY_SIZE(wr_arr); i++) { 591 wr = &wr_arr[i]; 592 wr->wr_cqe = cqe; 593 if (i) 594 /* Chain backwards */ 595 wr->next = &wr_arr[i - 1]; 596 } 597 598 return ib_post_recv(con->qp, wr, NULL); 599 } 600 601 static void rtrs_clt_rdma_done(struct ib_cq *cq, struct ib_wc *wc) 602 { 603 struct rtrs_clt_con *con = to_clt_con(wc->qp->qp_context); 604 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 605 u32 imm_type, imm_payload; 606 bool w_inval = false; 607 int err; 608 609 if (wc->status != IB_WC_SUCCESS) { 610 if (wc->status != IB_WC_WR_FLUSH_ERR) { 611 rtrs_err(clt_path->clt, "RDMA failed: %s\n", 612 ib_wc_status_msg(wc->status)); 613 rtrs_rdma_error_recovery(con); 614 } 615 return; 616 } 617 rtrs_clt_update_wc_stats(con); 618 619 switch (wc->opcode) { 620 case IB_WC_RECV_RDMA_WITH_IMM: 621 /* 622 * post_recv() RDMA write completions of IO reqs (read/write) 623 * and hb 624 */ 625 if (WARN_ON(wc->wr_cqe->done != rtrs_clt_rdma_done)) 626 return; 627 clt_path->s.hb_missed_cnt = 0; 628 rtrs_from_imm(be32_to_cpu(wc->ex.imm_data), 629 &imm_type, &imm_payload); 630 if (imm_type == RTRS_IO_RSP_IMM || 631 imm_type == RTRS_IO_RSP_W_INV_IMM) { 632 u32 msg_id; 633 634 w_inval = (imm_type == RTRS_IO_RSP_W_INV_IMM); 635 rtrs_from_io_rsp_imm(imm_payload, &msg_id, &err); 636 637 process_io_rsp(clt_path, msg_id, err, w_inval); 638 } else if (imm_type == RTRS_HB_MSG_IMM) { 639 WARN_ON(con->c.cid); 640 rtrs_send_hb_ack(&clt_path->s); 641 if (clt_path->flags & RTRS_MSG_NEW_RKEY_F) 642 return rtrs_clt_recv_done(con, wc); 643 } else if (imm_type == RTRS_HB_ACK_IMM) { 644 WARN_ON(con->c.cid); 645 clt_path->s.hb_cur_latency = 646 ktime_sub(ktime_get(), clt_path->s.hb_last_sent); 647 if (clt_path->flags & RTRS_MSG_NEW_RKEY_F) 648 return rtrs_clt_recv_done(con, wc); 649 } else { 650 rtrs_wrn(con->c.path, "Unknown IMM type %u\n", 651 imm_type); 652 } 653 if (w_inval) 654 /* 655 * Post x2 empty WRs: first is for this RDMA with IMM, 656 * second is for RECV with INV, which happened earlier. 657 */ 658 err = rtrs_post_recv_empty_x2(&con->c, &io_comp_cqe); 659 else 660 err = rtrs_post_recv_empty(&con->c, &io_comp_cqe); 661 if (err) { 662 rtrs_err(con->c.path, "rtrs_post_recv_empty(): %d\n", 663 err); 664 rtrs_rdma_error_recovery(con); 665 } 666 break; 667 case IB_WC_RECV: 668 /* 669 * Key invalidations from server side 670 */ 671 clt_path->s.hb_missed_cnt = 0; 672 WARN_ON(!(wc->wc_flags & IB_WC_WITH_INVALIDATE || 673 wc->wc_flags & IB_WC_WITH_IMM)); 674 WARN_ON(wc->wr_cqe->done != rtrs_clt_rdma_done); 675 if (clt_path->flags & RTRS_MSG_NEW_RKEY_F) { 676 if (wc->wc_flags & IB_WC_WITH_INVALIDATE) 677 return rtrs_clt_recv_done(con, wc); 678 679 return rtrs_clt_rkey_rsp_done(con, wc); 680 } 681 break; 682 case IB_WC_RDMA_WRITE: 683 /* 684 * post_send() RDMA write completions of IO reqs (read/write) 685 * and hb. 686 */ 687 break; 688 689 default: 690 rtrs_wrn(clt_path->clt, "Unexpected WC type: %d\n", wc->opcode); 691 return; 692 } 693 } 694 695 static int post_recv_io(struct rtrs_clt_con *con, size_t q_size) 696 { 697 int err, i; 698 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 699 700 for (i = 0; i < q_size; i++) { 701 if (clt_path->flags & RTRS_MSG_NEW_RKEY_F) { 702 struct rtrs_iu *iu = &con->rsp_ius[i]; 703 704 err = rtrs_iu_post_recv(&con->c, iu); 705 } else { 706 err = rtrs_post_recv_empty(&con->c, &io_comp_cqe); 707 } 708 if (err) 709 return err; 710 } 711 712 return 0; 713 } 714 715 static int post_recv_path(struct rtrs_clt_path *clt_path) 716 { 717 size_t q_size = 0; 718 int err, cid; 719 720 for (cid = 0; cid < clt_path->s.con_num; cid++) { 721 if (cid == 0) 722 q_size = SERVICE_CON_QUEUE_DEPTH; 723 else 724 q_size = clt_path->queue_depth; 725 726 /* 727 * x2 for RDMA read responses + FR key invalidations, 728 * RDMA writes do not require any FR registrations. 729 */ 730 q_size *= 2; 731 732 err = post_recv_io(to_clt_con(clt_path->s.con[cid]), q_size); 733 if (err) { 734 rtrs_err(clt_path->clt, "post_recv_io(), err: %d\n", 735 err); 736 return err; 737 } 738 } 739 740 return 0; 741 } 742 743 struct path_it { 744 int i; 745 struct list_head skip_list; 746 struct rtrs_clt_sess *clt; 747 struct rtrs_clt_path *(*next_path)(struct path_it *it); 748 }; 749 750 /* 751 * rtrs_clt_get_next_path_or_null - get clt path from the list or return NULL 752 * @head: the head for the list. 753 * @clt_path: The element to take the next clt_path from. 754 * 755 * Next clt path returned in round-robin fashion, i.e. head will be skipped, 756 * but if list is observed as empty, NULL will be returned. 757 * 758 * This function may safely run concurrently with the _rcu list-mutation 759 * primitives such as list_add_rcu() as long as it's guarded by rcu_read_lock(). 760 */ 761 static inline struct rtrs_clt_path * 762 rtrs_clt_get_next_path_or_null(struct list_head *head, struct rtrs_clt_path *clt_path) 763 { 764 return list_next_or_null_rcu(head, &clt_path->s.entry, typeof(*clt_path), s.entry) ?: 765 list_next_or_null_rcu(head, 766 READ_ONCE((&clt_path->s.entry)->next), 767 typeof(*clt_path), s.entry); 768 } 769 770 /** 771 * get_next_path_rr() - Returns path in round-robin fashion. 772 * @it: the path pointer 773 * 774 * Related to @MP_POLICY_RR 775 * 776 * Locks: 777 * rcu_read_lock() must be held. 778 */ 779 static struct rtrs_clt_path *get_next_path_rr(struct path_it *it) 780 { 781 struct rtrs_clt_path __rcu **ppcpu_path; 782 struct rtrs_clt_path *path; 783 struct rtrs_clt_sess *clt; 784 785 /* 786 * Assert that rcu lock must be held 787 */ 788 RCU_LOCKDEP_WARN(!rcu_read_lock_held(), "no rcu read lock held"); 789 790 clt = it->clt; 791 792 /* 793 * Here we use two RCU objects: @paths_list and @pcpu_path 794 * pointer. See rtrs_clt_remove_path_from_arr() for details 795 * how that is handled. 796 */ 797 798 ppcpu_path = this_cpu_ptr(clt->pcpu_path); 799 path = rcu_dereference(*ppcpu_path); 800 if (!path) 801 path = list_first_or_null_rcu(&clt->paths_list, 802 typeof(*path), s.entry); 803 else 804 path = rtrs_clt_get_next_path_or_null(&clt->paths_list, path); 805 806 rcu_assign_pointer(*ppcpu_path, path); 807 808 return path; 809 } 810 811 /** 812 * get_next_path_min_inflight() - Returns path with minimal inflight count. 813 * @it: the path pointer 814 * 815 * Related to @MP_POLICY_MIN_INFLIGHT 816 * 817 * Locks: 818 * rcu_read_lock() must be hold. 819 */ 820 static struct rtrs_clt_path *get_next_path_min_inflight(struct path_it *it) 821 { 822 struct rtrs_clt_path *min_path = NULL; 823 struct rtrs_clt_sess *clt = it->clt; 824 struct rtrs_clt_path *clt_path; 825 int min_inflight = INT_MAX; 826 int inflight; 827 828 list_for_each_entry_rcu(clt_path, &clt->paths_list, s.entry) { 829 if (READ_ONCE(clt_path->state) != RTRS_CLT_CONNECTED) 830 continue; 831 832 if (!list_empty(raw_cpu_ptr(clt_path->mp_skip_entry))) 833 continue; 834 835 inflight = atomic_read(&clt_path->stats->inflight); 836 837 if (inflight < min_inflight) { 838 min_inflight = inflight; 839 min_path = clt_path; 840 } 841 } 842 843 /* 844 * add the path to the skip list, so that next time we can get 845 * a different one 846 */ 847 if (min_path) 848 list_add(raw_cpu_ptr(min_path->mp_skip_entry), &it->skip_list); 849 850 return min_path; 851 } 852 853 /** 854 * get_next_path_min_latency() - Returns path with minimal latency. 855 * @it: the path pointer 856 * 857 * Return: a path with the lowest latency or NULL if all paths are tried 858 * 859 * Locks: 860 * rcu_read_lock() must be hold. 861 * 862 * Related to @MP_POLICY_MIN_LATENCY 863 * 864 * This DOES skip an already-tried path. 865 * There is a skip-list to skip a path if the path has tried but failed. 866 * It will try the minimum latency path and then the second minimum latency 867 * path and so on. Finally it will return NULL if all paths are tried. 868 * Therefore the caller MUST check the returned 869 * path is NULL and trigger the IO error. 870 */ 871 static struct rtrs_clt_path *get_next_path_min_latency(struct path_it *it) 872 { 873 struct rtrs_clt_path *min_path = NULL; 874 struct rtrs_clt_sess *clt = it->clt; 875 struct rtrs_clt_path *clt_path; 876 ktime_t min_latency = KTIME_MAX; 877 ktime_t latency; 878 879 list_for_each_entry_rcu(clt_path, &clt->paths_list, s.entry) { 880 if (READ_ONCE(clt_path->state) != RTRS_CLT_CONNECTED) 881 continue; 882 883 if (!list_empty(raw_cpu_ptr(clt_path->mp_skip_entry))) 884 continue; 885 886 latency = clt_path->s.hb_cur_latency; 887 888 if (latency < min_latency) { 889 min_latency = latency; 890 min_path = clt_path; 891 } 892 } 893 894 /* 895 * add the path to the skip list, so that next time we can get 896 * a different one 897 */ 898 if (min_path) 899 list_add(raw_cpu_ptr(min_path->mp_skip_entry), &it->skip_list); 900 901 return min_path; 902 } 903 904 static inline void path_it_init(struct path_it *it, struct rtrs_clt_sess *clt) 905 { 906 INIT_LIST_HEAD(&it->skip_list); 907 it->clt = clt; 908 it->i = 0; 909 910 if (clt->mp_policy == MP_POLICY_RR) 911 it->next_path = get_next_path_rr; 912 else if (clt->mp_policy == MP_POLICY_MIN_INFLIGHT) 913 it->next_path = get_next_path_min_inflight; 914 else 915 it->next_path = get_next_path_min_latency; 916 } 917 918 static inline void path_it_deinit(struct path_it *it) 919 { 920 struct list_head *skip, *tmp; 921 /* 922 * The skip_list is used only for the MIN_INFLIGHT and MIN_LATENCY policies. 923 * We need to remove paths from it, so that next IO can insert 924 * paths (->mp_skip_entry) into a skip_list again. 925 */ 926 list_for_each_safe(skip, tmp, &it->skip_list) 927 list_del_init(skip); 928 } 929 930 /** 931 * rtrs_clt_init_req() - Initialize an rtrs_clt_io_req holding information 932 * about an inflight IO. 933 * The user buffer holding user control message (not data) is copied into 934 * the corresponding buffer of rtrs_iu (req->iu->buf), which later on will 935 * also hold the control message of rtrs. 936 * @req: an io request holding information about IO. 937 * @clt_path: client path 938 * @conf: conformation callback function to notify upper layer. 939 * @permit: permit for allocation of RDMA remote buffer 940 * @priv: private pointer 941 * @vec: kernel vector containing control message 942 * @usr_len: length of the user message 943 * @sg: scater list for IO data 944 * @sg_cnt: number of scater list entries 945 * @data_len: length of the IO data 946 * @dir: direction of the IO. 947 */ 948 static void rtrs_clt_init_req(struct rtrs_clt_io_req *req, 949 struct rtrs_clt_path *clt_path, 950 void (*conf)(void *priv, int errno), 951 struct rtrs_permit *permit, void *priv, 952 const struct kvec *vec, size_t usr_len, 953 struct scatterlist *sg, size_t sg_cnt, 954 size_t data_len, int dir) 955 { 956 struct iov_iter iter; 957 size_t len; 958 959 req->permit = permit; 960 req->in_use = true; 961 req->usr_len = usr_len; 962 req->data_len = data_len; 963 req->sglist = sg; 964 req->sg_cnt = sg_cnt; 965 req->priv = priv; 966 req->dir = dir; 967 req->con = rtrs_permit_to_clt_con(clt_path, permit); 968 req->conf = conf; 969 req->mr->need_inval = false; 970 req->need_inv_comp = false; 971 req->inv_errno = 0; 972 refcount_set(&req->ref, 1); 973 req->mp_policy = clt_path->clt->mp_policy; 974 975 iov_iter_kvec(&iter, ITER_SOURCE, vec, 1, usr_len); 976 len = _copy_from_iter(req->iu->buf, usr_len, &iter); 977 WARN_ON(len != usr_len); 978 979 reinit_completion(&req->inv_comp); 980 } 981 982 static struct rtrs_clt_io_req * 983 rtrs_clt_get_req(struct rtrs_clt_path *clt_path, 984 void (*conf)(void *priv, int errno), 985 struct rtrs_permit *permit, void *priv, 986 const struct kvec *vec, size_t usr_len, 987 struct scatterlist *sg, size_t sg_cnt, 988 size_t data_len, int dir) 989 { 990 struct rtrs_clt_io_req *req; 991 992 req = &clt_path->reqs[permit->mem_id]; 993 rtrs_clt_init_req(req, clt_path, conf, permit, priv, vec, usr_len, 994 sg, sg_cnt, data_len, dir); 995 return req; 996 } 997 998 static struct rtrs_clt_io_req * 999 rtrs_clt_get_copy_req(struct rtrs_clt_path *alive_path, 1000 struct rtrs_clt_io_req *fail_req) 1001 { 1002 struct rtrs_clt_io_req *req; 1003 struct kvec vec = { 1004 .iov_base = fail_req->iu->buf, 1005 .iov_len = fail_req->usr_len 1006 }; 1007 1008 req = &alive_path->reqs[fail_req->permit->mem_id]; 1009 rtrs_clt_init_req(req, alive_path, fail_req->conf, fail_req->permit, 1010 fail_req->priv, &vec, fail_req->usr_len, 1011 fail_req->sglist, fail_req->sg_cnt, 1012 fail_req->data_len, fail_req->dir); 1013 return req; 1014 } 1015 1016 static int rtrs_post_rdma_write_sg(struct rtrs_clt_con *con, 1017 struct rtrs_clt_io_req *req, 1018 struct rtrs_rbuf *rbuf, bool fr_en, 1019 u32 count, u32 size, u32 imm, 1020 struct ib_send_wr *wr, 1021 struct ib_send_wr *tail) 1022 { 1023 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 1024 struct ib_sge *sge = req->sge; 1025 enum ib_send_flags flags; 1026 struct scatterlist *sg; 1027 size_t num_sge; 1028 int i; 1029 struct ib_send_wr *ptail = NULL; 1030 1031 if (fr_en) { 1032 i = 0; 1033 sge[i].addr = req->mr->iova; 1034 sge[i].length = req->mr->length; 1035 sge[i].lkey = req->mr->lkey; 1036 i++; 1037 num_sge = 2; 1038 ptail = tail; 1039 } else { 1040 for_each_sg(req->sglist, sg, count, i) { 1041 sge[i].addr = sg_dma_address(sg); 1042 sge[i].length = sg_dma_len(sg); 1043 sge[i].lkey = clt_path->s.dev->ib_pd->local_dma_lkey; 1044 } 1045 num_sge = 1 + count; 1046 } 1047 sge[i].addr = req->iu->dma_addr; 1048 sge[i].length = size; 1049 sge[i].lkey = clt_path->s.dev->ib_pd->local_dma_lkey; 1050 1051 /* 1052 * From time to time we have to post signalled sends, 1053 * or send queue will fill up and only QP reset can help. 1054 */ 1055 flags = atomic_inc_return(&con->c.wr_cnt) % clt_path->s.signal_interval ? 1056 0 : IB_SEND_SIGNALED; 1057 1058 ib_dma_sync_single_for_device(clt_path->s.dev->ib_dev, 1059 req->iu->dma_addr, 1060 size, DMA_TO_DEVICE); 1061 1062 return rtrs_iu_post_rdma_write_imm(&con->c, req->iu, sge, num_sge, 1063 rbuf->rkey, rbuf->addr, imm, 1064 flags, wr, ptail); 1065 } 1066 1067 static int rtrs_map_sg_fr(struct rtrs_clt_io_req *req, size_t count) 1068 { 1069 int nr; 1070 1071 /* Align the MR to a 4K page size to match the block virt boundary */ 1072 nr = ib_map_mr_sg(req->mr, req->sglist, count, NULL, SZ_4K); 1073 if (nr != count) 1074 return nr < 0 ? nr : -EINVAL; 1075 ib_update_fast_reg_key(req->mr, ib_inc_rkey(req->mr->rkey)); 1076 1077 return nr; 1078 } 1079 1080 static int rtrs_clt_write_req(struct rtrs_clt_io_req *req) 1081 { 1082 struct rtrs_clt_con *con = req->con; 1083 struct rtrs_path *s = con->c.path; 1084 struct rtrs_clt_path *clt_path = to_clt_path(s); 1085 struct rtrs_msg_rdma_write *msg; 1086 1087 struct rtrs_rbuf *rbuf; 1088 int ret, count = 0; 1089 u32 imm, buf_id; 1090 struct ib_reg_wr rwr; 1091 struct ib_send_wr *wr = NULL; 1092 bool fr_en = false; 1093 1094 const size_t tsize = sizeof(*msg) + req->data_len + req->usr_len; 1095 1096 if (tsize > clt_path->chunk_size) { 1097 rtrs_wrn(s, "Write request failed, size too big %zu > %d\n", 1098 tsize, clt_path->chunk_size); 1099 return -EMSGSIZE; 1100 } 1101 if (req->sg_cnt) { 1102 count = ib_dma_map_sg(clt_path->s.dev->ib_dev, req->sglist, 1103 req->sg_cnt, req->dir); 1104 if (!count) { 1105 rtrs_wrn(s, "Write request failed, map failed\n"); 1106 return -EINVAL; 1107 } 1108 } 1109 /* put rtrs msg after sg and user message */ 1110 msg = req->iu->buf + req->usr_len; 1111 msg->type = cpu_to_le16(RTRS_MSG_WRITE); 1112 msg->usr_len = cpu_to_le16(req->usr_len); 1113 1114 /* rtrs message on server side will be after user data and message */ 1115 imm = req->permit->mem_off + req->data_len + req->usr_len; 1116 imm = rtrs_to_io_req_imm(imm); 1117 buf_id = req->permit->mem_id; 1118 req->sg_size = tsize; 1119 rbuf = &clt_path->rbufs[buf_id]; 1120 1121 if (count) { 1122 ret = rtrs_map_sg_fr(req, count); 1123 if (ret < 0) { 1124 rtrs_err_rl(s, 1125 "Write request failed, failed to map fast reg. data, err: %d\n", 1126 ret); 1127 ib_dma_unmap_sg(clt_path->s.dev->ib_dev, req->sglist, 1128 req->sg_cnt, req->dir); 1129 return ret; 1130 } 1131 rwr = (struct ib_reg_wr) { 1132 .wr.opcode = IB_WR_REG_MR, 1133 .wr.wr_cqe = &fast_reg_cqe, 1134 .mr = req->mr, 1135 .key = req->mr->rkey, 1136 .access = (IB_ACCESS_LOCAL_WRITE), 1137 }; 1138 wr = &rwr.wr; 1139 fr_en = true; 1140 req->mr->need_inval = true; 1141 } 1142 /* 1143 * Update stats now, after request is successfully sent it is not 1144 * safe anymore to touch it. 1145 */ 1146 rtrs_clt_update_all_stats(req, WRITE); 1147 1148 ret = rtrs_post_rdma_write_sg(req->con, req, rbuf, fr_en, count, 1149 req->usr_len + sizeof(*msg), 1150 imm, wr, NULL); 1151 if (ret) { 1152 rtrs_err_rl(s, 1153 "Write request failed: error=%d path=%s [%s:%u]\n", 1154 ret, kobject_name(&clt_path->kobj), clt_path->hca_name, 1155 clt_path->hca_port); 1156 if (req->mp_policy == MP_POLICY_MIN_INFLIGHT) 1157 atomic_dec(&clt_path->stats->inflight); 1158 if (req->mr->need_inval) { 1159 req->mr->need_inval = false; 1160 refcount_dec(&req->ref); 1161 } 1162 if (req->sg_cnt) 1163 ib_dma_unmap_sg(clt_path->s.dev->ib_dev, req->sglist, 1164 req->sg_cnt, req->dir); 1165 } 1166 1167 return ret; 1168 } 1169 1170 static int rtrs_clt_read_req(struct rtrs_clt_io_req *req) 1171 { 1172 struct rtrs_clt_con *con = req->con; 1173 struct rtrs_path *s = con->c.path; 1174 struct rtrs_clt_path *clt_path = to_clt_path(s); 1175 struct rtrs_msg_rdma_read *msg; 1176 struct rtrs_ib_dev *dev = clt_path->s.dev; 1177 1178 struct ib_reg_wr rwr; 1179 struct ib_send_wr *wr = NULL; 1180 1181 int ret, count = 0; 1182 u32 imm, buf_id; 1183 1184 const size_t tsize = sizeof(*msg) + req->data_len + req->usr_len; 1185 1186 if (tsize > clt_path->chunk_size) { 1187 rtrs_wrn(s, 1188 "Read request failed, message size is %zu, bigger than CHUNK_SIZE %d\n", 1189 tsize, clt_path->chunk_size); 1190 return -EMSGSIZE; 1191 } 1192 1193 if (req->sg_cnt) { 1194 count = ib_dma_map_sg(dev->ib_dev, req->sglist, req->sg_cnt, 1195 req->dir); 1196 if (!count) { 1197 rtrs_wrn(s, 1198 "Read request failed, dma map failed\n"); 1199 return -EINVAL; 1200 } 1201 } 1202 /* put our message into req->buf after user message*/ 1203 msg = req->iu->buf + req->usr_len; 1204 msg->type = cpu_to_le16(RTRS_MSG_READ); 1205 msg->usr_len = cpu_to_le16(req->usr_len); 1206 1207 if (count) { 1208 ret = rtrs_map_sg_fr(req, count); 1209 if (ret < 0) { 1210 rtrs_err_rl(s, 1211 "Read request failed, failed to map fast reg. data, err: %d\n", 1212 ret); 1213 ib_dma_unmap_sg(dev->ib_dev, req->sglist, req->sg_cnt, 1214 req->dir); 1215 return ret; 1216 } 1217 rwr = (struct ib_reg_wr) { 1218 .wr.opcode = IB_WR_REG_MR, 1219 .wr.wr_cqe = &fast_reg_cqe, 1220 .mr = req->mr, 1221 .key = req->mr->rkey, 1222 .access = (IB_ACCESS_LOCAL_WRITE | 1223 IB_ACCESS_REMOTE_WRITE), 1224 }; 1225 wr = &rwr.wr; 1226 1227 msg->sg_cnt = cpu_to_le16(1); 1228 msg->flags = cpu_to_le16(RTRS_MSG_NEED_INVAL_F); 1229 1230 msg->desc[0].addr = cpu_to_le64(req->mr->iova); 1231 msg->desc[0].key = cpu_to_le32(req->mr->rkey); 1232 msg->desc[0].len = cpu_to_le32(req->mr->length); 1233 1234 /* Further invalidation is required */ 1235 req->mr->need_inval = !!RTRS_MSG_NEED_INVAL_F; 1236 1237 } else { 1238 msg->sg_cnt = 0; 1239 msg->flags = 0; 1240 } 1241 /* 1242 * rtrs message will be after the space reserved for disk data and 1243 * user message 1244 */ 1245 imm = req->permit->mem_off + req->data_len + req->usr_len; 1246 imm = rtrs_to_io_req_imm(imm); 1247 buf_id = req->permit->mem_id; 1248 1249 req->sg_size = sizeof(*msg); 1250 req->sg_size += le16_to_cpu(msg->sg_cnt) * sizeof(struct rtrs_sg_desc); 1251 req->sg_size += req->usr_len; 1252 1253 /* 1254 * Update stats now, after request is successfully sent it is not 1255 * safe anymore to touch it. 1256 */ 1257 rtrs_clt_update_all_stats(req, READ); 1258 1259 ret = rtrs_post_send_rdma(req->con, req, &clt_path->rbufs[buf_id], 1260 req->data_len, imm, wr); 1261 if (ret) { 1262 rtrs_err_rl(s, 1263 "Read request failed: error=%d path=%s [%s:%u]\n", 1264 ret, kobject_name(&clt_path->kobj), clt_path->hca_name, 1265 clt_path->hca_port); 1266 if (req->mp_policy == MP_POLICY_MIN_INFLIGHT) 1267 atomic_dec(&clt_path->stats->inflight); 1268 req->mr->need_inval = false; 1269 if (req->sg_cnt) 1270 ib_dma_unmap_sg(dev->ib_dev, req->sglist, 1271 req->sg_cnt, req->dir); 1272 } 1273 1274 return ret; 1275 } 1276 1277 /** 1278 * rtrs_clt_failover_req() - Try to find an active path for a failed request 1279 * @clt: clt context 1280 * @fail_req: a failed io request. 1281 */ 1282 static int rtrs_clt_failover_req(struct rtrs_clt_sess *clt, 1283 struct rtrs_clt_io_req *fail_req) 1284 { 1285 struct rtrs_clt_path *alive_path; 1286 struct rtrs_clt_io_req *req; 1287 int err = -ECONNABORTED; 1288 struct path_it it; 1289 1290 rcu_read_lock(); 1291 for (path_it_init(&it, clt); 1292 (alive_path = it.next_path(&it)) && it.i < it.clt->paths_num; 1293 it.i++) { 1294 if (READ_ONCE(alive_path->state) != RTRS_CLT_CONNECTED) 1295 continue; 1296 req = rtrs_clt_get_copy_req(alive_path, fail_req); 1297 if (req->dir == DMA_TO_DEVICE) 1298 err = rtrs_clt_write_req(req); 1299 else 1300 err = rtrs_clt_read_req(req); 1301 if (err) { 1302 req->in_use = false; 1303 continue; 1304 } 1305 /* Success path */ 1306 rtrs_clt_inc_failover_cnt(alive_path->stats); 1307 break; 1308 } 1309 path_it_deinit(&it); 1310 rcu_read_unlock(); 1311 1312 return err; 1313 } 1314 1315 static void fail_all_outstanding_reqs(struct rtrs_clt_path *clt_path) 1316 { 1317 struct rtrs_clt_sess *clt = clt_path->clt; 1318 struct rtrs_clt_io_req *req; 1319 int i, err; 1320 1321 if (!clt_path->reqs) 1322 return; 1323 for (i = 0; i < clt_path->queue_depth; ++i) { 1324 req = &clt_path->reqs[i]; 1325 if (!req->in_use) 1326 continue; 1327 1328 /* 1329 * Safely (without notification) complete failed request. 1330 * After completion this request is still useble and can 1331 * be failovered to another path. 1332 */ 1333 complete_rdma_req(req, -ECONNABORTED, false, true); 1334 1335 err = rtrs_clt_failover_req(clt, req); 1336 if (err) 1337 /* Failover failed, notify anyway */ 1338 req->conf(req->priv, err); 1339 } 1340 } 1341 1342 static void free_path_reqs(struct rtrs_clt_path *clt_path) 1343 { 1344 struct rtrs_clt_io_req *req; 1345 int i; 1346 1347 if (!clt_path->reqs) 1348 return; 1349 for (i = 0; i < clt_path->queue_depth; ++i) { 1350 req = &clt_path->reqs[i]; 1351 if (req->mr) 1352 ib_dereg_mr(req->mr); 1353 kfree(req->sge); 1354 rtrs_iu_free(req->iu, clt_path->s.dev->ib_dev, 1); 1355 } 1356 kfree(clt_path->reqs); 1357 clt_path->reqs = NULL; 1358 } 1359 1360 static int alloc_path_reqs(struct rtrs_clt_path *clt_path) 1361 { 1362 struct rtrs_clt_io_req *req; 1363 int i, err = -ENOMEM; 1364 1365 clt_path->reqs = kcalloc(clt_path->queue_depth, 1366 sizeof(*clt_path->reqs), 1367 GFP_KERNEL); 1368 if (!clt_path->reqs) 1369 return -ENOMEM; 1370 1371 for (i = 0; i < clt_path->queue_depth; ++i) { 1372 req = &clt_path->reqs[i]; 1373 req->iu = rtrs_iu_alloc(1, clt_path->max_hdr_size, GFP_KERNEL, 1374 clt_path->s.dev->ib_dev, 1375 DMA_TO_DEVICE, 1376 rtrs_clt_rdma_done); 1377 if (!req->iu) 1378 goto out; 1379 1380 req->sge = kcalloc(2, sizeof(*req->sge), GFP_KERNEL); 1381 if (!req->sge) 1382 goto out; 1383 1384 req->mr = ib_alloc_mr(clt_path->s.dev->ib_pd, 1385 IB_MR_TYPE_MEM_REG, 1386 clt_path->max_pages_per_mr); 1387 if (IS_ERR(req->mr)) { 1388 err = PTR_ERR(req->mr); 1389 pr_err("Failed to alloc clt_path->max_pages_per_mr %d: %pe\n", 1390 clt_path->max_pages_per_mr, req->mr); 1391 req->mr = NULL; 1392 goto out; 1393 } 1394 1395 init_completion(&req->inv_comp); 1396 } 1397 1398 return 0; 1399 1400 out: 1401 free_path_reqs(clt_path); 1402 1403 return err; 1404 } 1405 1406 static int alloc_permits(struct rtrs_clt_sess *clt) 1407 { 1408 unsigned int chunk_bits; 1409 int err, i; 1410 1411 clt->permits_map = bitmap_zalloc(clt->queue_depth, GFP_KERNEL); 1412 if (!clt->permits_map) { 1413 err = -ENOMEM; 1414 goto out_err; 1415 } 1416 clt->permits = kcalloc(clt->queue_depth, permit_size(clt), GFP_KERNEL); 1417 if (!clt->permits) { 1418 err = -ENOMEM; 1419 goto err_map; 1420 } 1421 chunk_bits = ilog2(clt->queue_depth - 1) + 1; 1422 for (i = 0; i < clt->queue_depth; i++) { 1423 struct rtrs_permit *permit; 1424 1425 permit = get_permit(clt, i); 1426 permit->mem_id = i; 1427 permit->mem_off = i << (MAX_IMM_PAYL_BITS - chunk_bits); 1428 } 1429 1430 return 0; 1431 1432 err_map: 1433 bitmap_free(clt->permits_map); 1434 clt->permits_map = NULL; 1435 out_err: 1436 return err; 1437 } 1438 1439 static void free_permits(struct rtrs_clt_sess *clt) 1440 { 1441 if (clt->permits_map) 1442 wait_event(clt->permits_wait, 1443 bitmap_empty(clt->permits_map, clt->queue_depth)); 1444 1445 bitmap_free(clt->permits_map); 1446 clt->permits_map = NULL; 1447 kfree(clt->permits); 1448 clt->permits = NULL; 1449 } 1450 1451 static void query_fast_reg_mode(struct rtrs_clt_path *clt_path) 1452 { 1453 struct ib_device *ib_dev; 1454 u64 max_pages_per_mr; 1455 int mr_page_shift; 1456 1457 ib_dev = clt_path->s.dev->ib_dev; 1458 1459 /* 1460 * Use the smallest page size supported by the HCA, down to a 1461 * minimum of 4096 bytes. We're unlikely to build large sglists 1462 * out of smaller entries. 1463 */ 1464 mr_page_shift = max(12, ffs(ib_dev->attrs.page_size_cap) - 1); 1465 max_pages_per_mr = ib_dev->attrs.max_mr_size; 1466 do_div(max_pages_per_mr, (1ull << mr_page_shift)); 1467 clt_path->max_pages_per_mr = 1468 min3(clt_path->max_pages_per_mr, (u32)max_pages_per_mr, 1469 ib_dev->attrs.max_fast_reg_page_list_len); 1470 clt_path->clt->max_segments = 1471 min(clt_path->max_pages_per_mr, clt_path->clt->max_segments); 1472 } 1473 1474 static bool rtrs_clt_change_state_get_old(struct rtrs_clt_path *clt_path, 1475 enum rtrs_clt_state new_state, 1476 enum rtrs_clt_state *old_state) 1477 { 1478 bool changed; 1479 1480 spin_lock_irq(&clt_path->state_wq.lock); 1481 if (old_state) 1482 *old_state = clt_path->state; 1483 changed = rtrs_clt_change_state(clt_path, new_state); 1484 spin_unlock_irq(&clt_path->state_wq.lock); 1485 1486 return changed; 1487 } 1488 1489 static void rtrs_clt_hb_err_handler(struct rtrs_con *c) 1490 { 1491 struct rtrs_clt_con *con = container_of(c, typeof(*con), c); 1492 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 1493 1494 rtrs_err(con->c.path, "HB err handler for path=%s\n", kobject_name(&clt_path->kobj)); 1495 rtrs_rdma_error_recovery(con); 1496 } 1497 1498 static void rtrs_clt_init_hb(struct rtrs_clt_path *clt_path) 1499 { 1500 rtrs_init_hb(&clt_path->s, &io_comp_cqe, 1501 RTRS_HB_INTERVAL_MS, 1502 RTRS_HB_MISSED_MAX, 1503 rtrs_clt_hb_err_handler, 1504 rtrs_wq); 1505 } 1506 1507 static void rtrs_clt_reconnect_work(struct work_struct *work); 1508 static void rtrs_clt_close_work(struct work_struct *work); 1509 1510 static void rtrs_clt_err_recovery_work(struct work_struct *work) 1511 { 1512 struct rtrs_clt_path *clt_path; 1513 struct rtrs_clt_sess *clt; 1514 int delay_ms; 1515 1516 clt_path = container_of(work, struct rtrs_clt_path, err_recovery_work); 1517 clt = clt_path->clt; 1518 delay_ms = clt->reconnect_delay_sec * 1000; 1519 rtrs_clt_stop_and_destroy_conns(clt_path); 1520 queue_delayed_work(rtrs_wq, &clt_path->reconnect_dwork, 1521 msecs_to_jiffies(delay_ms + 1522 get_random_u32_below(RTRS_RECONNECT_SEED))); 1523 } 1524 1525 static struct rtrs_clt_path *alloc_path(struct rtrs_clt_sess *clt, 1526 const struct rtrs_addr *path, 1527 size_t con_num, u32 nr_poll_queues) 1528 { 1529 struct rtrs_clt_path *clt_path; 1530 int err = -ENOMEM; 1531 int cpu; 1532 size_t total_con; 1533 1534 clt_path = kzalloc(sizeof(*clt_path), GFP_KERNEL); 1535 if (!clt_path) 1536 goto err; 1537 1538 /* 1539 * irqmode and poll 1540 * +1: Extra connection for user messages 1541 */ 1542 total_con = con_num + nr_poll_queues + 1; 1543 clt_path->s.con = kcalloc(total_con, sizeof(*clt_path->s.con), 1544 GFP_KERNEL); 1545 if (!clt_path->s.con) 1546 goto err_free_path; 1547 1548 clt_path->s.con_num = total_con; 1549 clt_path->s.irq_con_num = con_num + 1; 1550 1551 clt_path->stats = kzalloc(sizeof(*clt_path->stats), GFP_KERNEL); 1552 if (!clt_path->stats) 1553 goto err_free_con; 1554 1555 mutex_init(&clt_path->init_mutex); 1556 uuid_gen(&clt_path->s.uuid); 1557 memcpy(&clt_path->s.dst_addr, path->dst, 1558 rdma_addr_size((struct sockaddr *)path->dst)); 1559 1560 /* 1561 * rdma_resolve_addr() passes src_addr to cma_bind_addr, which 1562 * checks the sa_family to be non-zero. If user passed src_addr=NULL 1563 * the sess->src_addr will contain only zeros, which is then fine. 1564 */ 1565 if (path->src) 1566 memcpy(&clt_path->s.src_addr, path->src, 1567 rdma_addr_size((struct sockaddr *)path->src)); 1568 strscpy(clt_path->s.sessname, clt->sessname, 1569 sizeof(clt_path->s.sessname)); 1570 clt_path->clt = clt; 1571 clt_path->max_pages_per_mr = RTRS_MAX_SEGMENTS; 1572 init_waitqueue_head(&clt_path->state_wq); 1573 clt_path->state = RTRS_CLT_CONNECTING; 1574 atomic_set(&clt_path->connected_cnt, 0); 1575 INIT_WORK(&clt_path->close_work, rtrs_clt_close_work); 1576 INIT_WORK(&clt_path->err_recovery_work, rtrs_clt_err_recovery_work); 1577 INIT_DELAYED_WORK(&clt_path->reconnect_dwork, rtrs_clt_reconnect_work); 1578 rtrs_clt_init_hb(clt_path); 1579 1580 clt_path->mp_skip_entry = alloc_percpu(typeof(*clt_path->mp_skip_entry)); 1581 if (!clt_path->mp_skip_entry) 1582 goto err_free_stats; 1583 1584 for_each_possible_cpu(cpu) 1585 INIT_LIST_HEAD(per_cpu_ptr(clt_path->mp_skip_entry, cpu)); 1586 1587 err = rtrs_clt_init_stats(clt_path->stats); 1588 if (err) 1589 goto err_free_percpu; 1590 1591 return clt_path; 1592 1593 err_free_percpu: 1594 free_percpu(clt_path->mp_skip_entry); 1595 err_free_stats: 1596 kfree(clt_path->stats); 1597 err_free_con: 1598 kfree(clt_path->s.con); 1599 err_free_path: 1600 kfree(clt_path); 1601 err: 1602 return ERR_PTR(err); 1603 } 1604 1605 void free_path(struct rtrs_clt_path *clt_path) 1606 { 1607 free_percpu(clt_path->mp_skip_entry); 1608 mutex_destroy(&clt_path->init_mutex); 1609 kfree(clt_path->s.con); 1610 kfree(clt_path->rbufs); 1611 kfree(clt_path); 1612 } 1613 1614 static int create_con(struct rtrs_clt_path *clt_path, unsigned int cid) 1615 { 1616 struct rtrs_clt_con *con; 1617 1618 con = kzalloc(sizeof(*con), GFP_KERNEL); 1619 if (!con) 1620 return -ENOMEM; 1621 1622 /* Map first two connections to the first CPU */ 1623 con->cpu = (cid ? cid - 1 : 0) % nr_cpu_ids; 1624 con->c.cid = cid; 1625 con->c.path = &clt_path->s; 1626 /* Align with srv, init as 1 */ 1627 atomic_set(&con->c.wr_cnt, 1); 1628 mutex_init(&con->con_mutex); 1629 1630 clt_path->s.con[cid] = &con->c; 1631 1632 return 0; 1633 } 1634 1635 static void destroy_con(struct rtrs_clt_con *con) 1636 { 1637 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 1638 1639 clt_path->s.con[con->c.cid] = NULL; 1640 mutex_destroy(&con->con_mutex); 1641 kfree(con); 1642 } 1643 1644 static int create_con_cq_qp(struct rtrs_clt_con *con) 1645 { 1646 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 1647 u32 max_send_wr, max_recv_wr, cq_num, max_send_sge, wr_limit; 1648 int err, cq_vector; 1649 struct rtrs_msg_rkey_rsp *rsp; 1650 1651 lockdep_assert_held(&con->con_mutex); 1652 if (con->c.cid == 0) { 1653 max_send_sge = 1; 1654 /* We must be the first here */ 1655 if (WARN_ON(clt_path->s.dev)) 1656 return -EINVAL; 1657 1658 /* 1659 * The whole session uses device from user connection. 1660 * Be careful not to close user connection before ib dev 1661 * is gracefully put. 1662 */ 1663 clt_path->s.dev = rtrs_ib_dev_find_or_add(con->c.cm_id->device, 1664 &dev_pd); 1665 if (!clt_path->s.dev) { 1666 rtrs_wrn(clt_path->clt, 1667 "rtrs_ib_dev_find_get_or_add(): no memory\n"); 1668 return -ENOMEM; 1669 } 1670 clt_path->s.dev_ref = 1; 1671 query_fast_reg_mode(clt_path); 1672 wr_limit = clt_path->s.dev->ib_dev->attrs.max_qp_wr; 1673 /* 1674 * Two (request + registration) completion for send 1675 * Two for recv if always_invalidate is set on server 1676 * or one for recv. 1677 * + 2 for drain and heartbeat 1678 * in case qp gets into error state. 1679 */ 1680 max_send_wr = 1681 min_t(int, wr_limit, SERVICE_CON_QUEUE_DEPTH * 2 + 2); 1682 max_recv_wr = max_send_wr; 1683 } else { 1684 /* 1685 * Here we assume that session members are correctly set. 1686 * This is always true if user connection (cid == 0) is 1687 * established first. 1688 */ 1689 if (WARN_ON(!clt_path->s.dev)) 1690 return -EINVAL; 1691 if (WARN_ON(!clt_path->queue_depth)) 1692 return -EINVAL; 1693 1694 wr_limit = clt_path->s.dev->ib_dev->attrs.max_qp_wr; 1695 /* Shared between connections */ 1696 clt_path->s.dev_ref++; 1697 max_send_wr = min_t(int, wr_limit, 1698 /* QD * (REQ + RSP + FR REGS or INVS) + drain */ 1699 clt_path->queue_depth * 4 + 1); 1700 max_recv_wr = min_t(int, wr_limit, 1701 clt_path->queue_depth * 3 + 1); 1702 max_send_sge = 2; 1703 } 1704 atomic_set(&con->c.sq_wr_avail, max_send_wr); 1705 cq_num = max_send_wr + max_recv_wr; 1706 /* alloc iu to recv new rkey reply when server reports flags set */ 1707 if (clt_path->flags & RTRS_MSG_NEW_RKEY_F || con->c.cid == 0) { 1708 con->rsp_ius = rtrs_iu_alloc(cq_num, sizeof(*rsp), 1709 GFP_KERNEL, 1710 clt_path->s.dev->ib_dev, 1711 DMA_FROM_DEVICE, 1712 rtrs_clt_rdma_done); 1713 if (!con->rsp_ius) 1714 return -ENOMEM; 1715 con->queue_num = cq_num; 1716 } 1717 cq_vector = con->cpu % clt_path->s.dev->ib_dev->num_comp_vectors; 1718 if (con->c.cid >= clt_path->s.irq_con_num) 1719 err = rtrs_cq_qp_create(&clt_path->s, &con->c, max_send_sge, 1720 cq_vector, cq_num, max_send_wr, 1721 max_recv_wr, IB_POLL_DIRECT); 1722 else 1723 err = rtrs_cq_qp_create(&clt_path->s, &con->c, max_send_sge, 1724 cq_vector, cq_num, max_send_wr, 1725 max_recv_wr, IB_POLL_SOFTIRQ); 1726 /* 1727 * In case of error we do not bother to clean previous allocations, 1728 * since destroy_con_cq_qp() must be called. 1729 */ 1730 return err; 1731 } 1732 1733 static void destroy_con_cq_qp(struct rtrs_clt_con *con) 1734 { 1735 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 1736 1737 /* 1738 * Be careful here: destroy_con_cq_qp() can be called even 1739 * create_con_cq_qp() failed, see comments there. 1740 */ 1741 lockdep_assert_held(&con->con_mutex); 1742 rtrs_cq_qp_destroy(&con->c); 1743 if (con->rsp_ius) { 1744 rtrs_iu_free(con->rsp_ius, clt_path->s.dev->ib_dev, 1745 con->queue_num); 1746 con->rsp_ius = NULL; 1747 con->queue_num = 0; 1748 } 1749 if (clt_path->s.dev_ref && !--clt_path->s.dev_ref) { 1750 rtrs_ib_dev_put(clt_path->s.dev); 1751 clt_path->s.dev = NULL; 1752 } 1753 } 1754 1755 static void stop_cm(struct rtrs_clt_con *con) 1756 { 1757 rdma_disconnect(con->c.cm_id); 1758 if (con->c.qp) 1759 ib_drain_qp(con->c.qp); 1760 } 1761 1762 static void destroy_cm(struct rtrs_clt_con *con) 1763 { 1764 rdma_destroy_id(con->c.cm_id); 1765 con->c.cm_id = NULL; 1766 } 1767 1768 static int rtrs_rdma_addr_resolved(struct rtrs_clt_con *con) 1769 { 1770 struct rtrs_path *s = con->c.path; 1771 int err; 1772 1773 mutex_lock(&con->con_mutex); 1774 err = create_con_cq_qp(con); 1775 mutex_unlock(&con->con_mutex); 1776 if (err) { 1777 rtrs_err(s, "create_con_cq_qp(), err: %d\n", err); 1778 return err; 1779 } 1780 err = rdma_resolve_route(con->c.cm_id, RTRS_CONNECT_TIMEOUT_MS); 1781 if (err) 1782 rtrs_err(s, "Resolving route failed, err: %d\n", err); 1783 1784 return err; 1785 } 1786 1787 static int rtrs_rdma_route_resolved(struct rtrs_clt_con *con) 1788 { 1789 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 1790 struct rtrs_clt_sess *clt = clt_path->clt; 1791 struct rtrs_msg_conn_req msg; 1792 struct rdma_conn_param param; 1793 1794 int err; 1795 1796 param = (struct rdma_conn_param) { 1797 .retry_count = 7, 1798 .rnr_retry_count = 7, 1799 .private_data = &msg, 1800 .private_data_len = sizeof(msg), 1801 }; 1802 1803 msg = (struct rtrs_msg_conn_req) { 1804 .magic = cpu_to_le16(RTRS_MAGIC), 1805 .version = cpu_to_le16(RTRS_PROTO_VER), 1806 .cid = cpu_to_le16(con->c.cid), 1807 .cid_num = cpu_to_le16(clt_path->s.con_num), 1808 .recon_cnt = cpu_to_le16(clt_path->s.recon_cnt), 1809 }; 1810 msg.first_conn = clt_path->for_new_clt ? FIRST_CONN : 0; 1811 uuid_copy(&msg.sess_uuid, &clt_path->s.uuid); 1812 uuid_copy(&msg.paths_uuid, &clt->paths_uuid); 1813 1814 err = rdma_connect_locked(con->c.cm_id, ¶m); 1815 if (err) 1816 rtrs_err(clt, "rdma_connect_locked(): %d\n", err); 1817 1818 return err; 1819 } 1820 1821 static int rtrs_rdma_conn_established(struct rtrs_clt_con *con, 1822 struct rdma_cm_event *ev) 1823 { 1824 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 1825 struct rtrs_clt_sess *clt = clt_path->clt; 1826 const struct rtrs_msg_conn_rsp *msg; 1827 u16 version, queue_depth; 1828 int errno; 1829 u8 len; 1830 1831 msg = ev->param.conn.private_data; 1832 len = ev->param.conn.private_data_len; 1833 if (len < sizeof(*msg)) { 1834 rtrs_err(clt, "Invalid RTRS connection response\n"); 1835 return -ECONNRESET; 1836 } 1837 if (le16_to_cpu(msg->magic) != RTRS_MAGIC) { 1838 rtrs_err(clt, "Invalid RTRS magic\n"); 1839 return -ECONNRESET; 1840 } 1841 version = le16_to_cpu(msg->version); 1842 if (version >> 8 != RTRS_PROTO_VER_MAJOR) { 1843 rtrs_err(clt, "Unsupported major RTRS version: %d, expected %d\n", 1844 version >> 8, RTRS_PROTO_VER_MAJOR); 1845 return -ECONNRESET; 1846 } 1847 errno = le16_to_cpu(msg->errno); 1848 if (errno) { 1849 rtrs_err(clt, "Invalid RTRS message: errno %d\n", 1850 errno); 1851 return -ECONNRESET; 1852 } 1853 if (con->c.cid == 0) { 1854 queue_depth = le16_to_cpu(msg->queue_depth); 1855 1856 if (clt_path->queue_depth > 0 && queue_depth != clt_path->queue_depth) { 1857 rtrs_err(clt, "Error: queue depth changed\n"); 1858 1859 /* 1860 * Stop any more reconnection attempts 1861 */ 1862 clt_path->reconnect_attempts = -1; 1863 rtrs_err(clt, 1864 "Disabling auto-reconnect. Trigger a manual reconnect after issue is resolved\n"); 1865 return -ECONNRESET; 1866 } 1867 1868 if (!clt_path->rbufs) { 1869 clt_path->rbufs = kcalloc(queue_depth, 1870 sizeof(*clt_path->rbufs), 1871 GFP_KERNEL); 1872 if (!clt_path->rbufs) 1873 return -ENOMEM; 1874 } 1875 clt_path->queue_depth = queue_depth; 1876 clt_path->s.signal_interval = min_not_zero(queue_depth, 1877 (unsigned short) SERVICE_CON_QUEUE_DEPTH); 1878 clt_path->max_hdr_size = le32_to_cpu(msg->max_hdr_size); 1879 clt_path->max_io_size = le32_to_cpu(msg->max_io_size); 1880 clt_path->flags = le32_to_cpu(msg->flags); 1881 clt_path->chunk_size = clt_path->max_io_size + clt_path->max_hdr_size; 1882 1883 /* 1884 * Global IO size is always a minimum. 1885 * If while a reconnection server sends us a value a bit 1886 * higher - client does not care and uses cached minimum. 1887 * 1888 * Since we can have several sessions (paths) restablishing 1889 * connections in parallel, use lock. 1890 */ 1891 mutex_lock(&clt->paths_mutex); 1892 clt->queue_depth = clt_path->queue_depth; 1893 clt->max_io_size = min_not_zero(clt_path->max_io_size, 1894 clt->max_io_size); 1895 mutex_unlock(&clt->paths_mutex); 1896 1897 /* 1898 * Cache the hca_port and hca_name for sysfs 1899 */ 1900 clt_path->hca_port = con->c.cm_id->port_num; 1901 scnprintf(clt_path->hca_name, sizeof(clt_path->hca_name), 1902 clt_path->s.dev->ib_dev->name); 1903 clt_path->s.src_addr = con->c.cm_id->route.addr.src_addr; 1904 /* set for_new_clt, to allow future reconnect on any path */ 1905 clt_path->for_new_clt = 1; 1906 } 1907 1908 return 0; 1909 } 1910 1911 static inline void flag_success_on_conn(struct rtrs_clt_con *con) 1912 { 1913 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 1914 1915 atomic_inc(&clt_path->connected_cnt); 1916 con->cm_err = 1; 1917 } 1918 1919 static int rtrs_rdma_conn_rejected(struct rtrs_clt_con *con, 1920 struct rdma_cm_event *ev) 1921 { 1922 struct rtrs_path *s = con->c.path; 1923 const struct rtrs_msg_conn_rsp *msg; 1924 const char *rej_msg; 1925 int status, errno; 1926 u8 data_len; 1927 1928 status = ev->status; 1929 rej_msg = rdma_reject_msg(con->c.cm_id, status); 1930 msg = rdma_consumer_reject_data(con->c.cm_id, ev, &data_len); 1931 1932 if (msg && data_len >= sizeof(*msg)) { 1933 errno = (int16_t)le16_to_cpu(msg->errno); 1934 if (errno == -EBUSY) 1935 rtrs_err(s, 1936 "Previous session is still exists on the server, please reconnect later\n"); 1937 else 1938 rtrs_err(s, 1939 "Connect rejected: status %d (%s), rtrs errno %d\n", 1940 status, rej_msg, errno); 1941 } else { 1942 rtrs_err(s, 1943 "Connect rejected but with malformed message: status %d (%s)\n", 1944 status, rej_msg); 1945 } 1946 1947 return -ECONNRESET; 1948 } 1949 1950 void rtrs_clt_close_conns(struct rtrs_clt_path *clt_path, bool wait) 1951 { 1952 trace_rtrs_clt_close_conns(clt_path); 1953 1954 if (rtrs_clt_change_state_get_old(clt_path, RTRS_CLT_CLOSING, NULL)) 1955 queue_work(rtrs_wq, &clt_path->close_work); 1956 if (wait) 1957 flush_work(&clt_path->close_work); 1958 } 1959 1960 static inline void flag_error_on_conn(struct rtrs_clt_con *con, int cm_err) 1961 { 1962 if (con->cm_err == 1) { 1963 struct rtrs_clt_path *clt_path; 1964 1965 clt_path = to_clt_path(con->c.path); 1966 if (atomic_dec_and_test(&clt_path->connected_cnt)) 1967 1968 wake_up(&clt_path->state_wq); 1969 } 1970 con->cm_err = cm_err; 1971 } 1972 1973 static int rtrs_clt_rdma_cm_handler(struct rdma_cm_id *cm_id, 1974 struct rdma_cm_event *ev) 1975 { 1976 struct rtrs_clt_con *con = cm_id->context; 1977 struct rtrs_path *s = con->c.path; 1978 struct rtrs_clt_path *clt_path = to_clt_path(s); 1979 int cm_err = 0; 1980 1981 switch (ev->event) { 1982 case RDMA_CM_EVENT_ADDR_RESOLVED: 1983 cm_err = rtrs_rdma_addr_resolved(con); 1984 break; 1985 case RDMA_CM_EVENT_ROUTE_RESOLVED: 1986 cm_err = rtrs_rdma_route_resolved(con); 1987 break; 1988 case RDMA_CM_EVENT_ESTABLISHED: 1989 cm_err = rtrs_rdma_conn_established(con, ev); 1990 if (!cm_err) { 1991 /* 1992 * Report success and wake up. Here we abuse state_wq, 1993 * i.e. wake up without state change, but we set cm_err. 1994 */ 1995 flag_success_on_conn(con); 1996 wake_up(&clt_path->state_wq); 1997 return 0; 1998 } 1999 break; 2000 case RDMA_CM_EVENT_REJECTED: 2001 cm_err = rtrs_rdma_conn_rejected(con, ev); 2002 break; 2003 case RDMA_CM_EVENT_DISCONNECTED: 2004 /* No message for disconnecting */ 2005 cm_err = -ECONNRESET; 2006 break; 2007 case RDMA_CM_EVENT_CONNECT_ERROR: 2008 case RDMA_CM_EVENT_UNREACHABLE: 2009 case RDMA_CM_EVENT_ADDR_CHANGE: 2010 case RDMA_CM_EVENT_TIMEWAIT_EXIT: 2011 rtrs_wrn(s, "CM error (CM event: %s, err: %d)\n", 2012 rdma_event_msg(ev->event), ev->status); 2013 cm_err = -ECONNRESET; 2014 break; 2015 case RDMA_CM_EVENT_ADDR_ERROR: 2016 case RDMA_CM_EVENT_ROUTE_ERROR: 2017 rtrs_wrn(s, "CM error (CM event: %s, err: %d)\n", 2018 rdma_event_msg(ev->event), ev->status); 2019 cm_err = -EHOSTUNREACH; 2020 break; 2021 case RDMA_CM_EVENT_DEVICE_REMOVAL: 2022 /* 2023 * Device removal is a special case. Queue close and return 0. 2024 */ 2025 rtrs_wrn_rl(s, "CM event: %s, status: %d\n", rdma_event_msg(ev->event), 2026 ev->status); 2027 rtrs_clt_close_conns(clt_path, false); 2028 return 0; 2029 default: 2030 rtrs_err(s, "Unexpected RDMA CM error (CM event: %s, err: %d)\n", 2031 rdma_event_msg(ev->event), ev->status); 2032 cm_err = -ECONNRESET; 2033 break; 2034 } 2035 2036 if (cm_err) { 2037 /* 2038 * cm error makes sense only on connection establishing, 2039 * in other cases we rely on normal procedure of reconnecting. 2040 */ 2041 flag_error_on_conn(con, cm_err); 2042 rtrs_rdma_error_recovery(con); 2043 } 2044 2045 return 0; 2046 } 2047 2048 /* The caller should do the cleanup in case of error */ 2049 static int create_cm(struct rtrs_clt_con *con) 2050 { 2051 struct rtrs_path *s = con->c.path; 2052 struct rtrs_clt_path *clt_path = to_clt_path(s); 2053 struct rdma_cm_id *cm_id; 2054 int err; 2055 2056 cm_id = rdma_create_id(&init_net, rtrs_clt_rdma_cm_handler, con, 2057 clt_path->s.dst_addr.ss_family == AF_IB ? 2058 RDMA_PS_IB : RDMA_PS_TCP, IB_QPT_RC); 2059 if (IS_ERR(cm_id)) { 2060 rtrs_err(s, "Failed to create CM ID, err: %pe\n", cm_id); 2061 return PTR_ERR(cm_id); 2062 } 2063 con->c.cm_id = cm_id; 2064 con->cm_err = 0; 2065 /* allow the port to be reused */ 2066 err = rdma_set_reuseaddr(cm_id, 1); 2067 if (err != 0) { 2068 rtrs_err(s, "Set address reuse failed, err: %d\n", err); 2069 return err; 2070 } 2071 err = rdma_resolve_addr(cm_id, (struct sockaddr *)&clt_path->s.src_addr, 2072 (struct sockaddr *)&clt_path->s.dst_addr, 2073 RTRS_CONNECT_TIMEOUT_MS); 2074 if (err) { 2075 rtrs_err(s, "Failed to resolve address, err: %d\n", err); 2076 return err; 2077 } 2078 /* 2079 * Combine connection status and session events. This is needed 2080 * for waiting two possible cases: cm_err has something meaningful 2081 * or session state was really changed to error by device removal. 2082 */ 2083 err = wait_event_interruptible_timeout( 2084 clt_path->state_wq, 2085 con->cm_err || clt_path->state != RTRS_CLT_CONNECTING, 2086 msecs_to_jiffies(RTRS_CONNECT_TIMEOUT_MS)); 2087 if (err == 0 || err == -ERESTARTSYS) { 2088 if (err == 0) 2089 err = -ETIMEDOUT; 2090 /* Timedout or interrupted */ 2091 return err; 2092 } 2093 if (con->cm_err < 0) 2094 return con->cm_err; 2095 if (READ_ONCE(clt_path->state) != RTRS_CLT_CONNECTING) 2096 /* Device removal */ 2097 return -ECONNABORTED; 2098 2099 return 0; 2100 } 2101 2102 static void rtrs_clt_path_up(struct rtrs_clt_path *clt_path) 2103 { 2104 struct rtrs_clt_sess *clt = clt_path->clt; 2105 int up; 2106 2107 /* 2108 * We can fire RECONNECTED event only when all paths were 2109 * connected on rtrs_clt_open(), then each was disconnected 2110 * and the first one connected again. That's why this nasty 2111 * game with counter value. 2112 */ 2113 2114 mutex_lock(&clt->paths_ev_mutex); 2115 up = ++clt->paths_up; 2116 /* 2117 * Here it is safe to access paths num directly since up counter 2118 * is greater than MAX_PATHS_NUM only while rtrs_clt_open() is 2119 * in progress, thus paths removals are impossible. 2120 */ 2121 if (up > MAX_PATHS_NUM && up == MAX_PATHS_NUM + clt->paths_num) 2122 clt->paths_up = clt->paths_num; 2123 else if (up == 1) 2124 clt->link_ev(clt->priv, RTRS_CLT_LINK_EV_RECONNECTED); 2125 mutex_unlock(&clt->paths_ev_mutex); 2126 2127 /* Mark session as established */ 2128 clt_path->established = true; 2129 clt_path->reconnect_attempts = 0; 2130 clt_path->stats->reconnects.successful_cnt++; 2131 } 2132 2133 static void rtrs_clt_path_down(struct rtrs_clt_path *clt_path) 2134 { 2135 struct rtrs_clt_sess *clt = clt_path->clt; 2136 2137 if (!clt_path->established) 2138 return; 2139 2140 clt_path->established = false; 2141 mutex_lock(&clt->paths_ev_mutex); 2142 WARN_ON(!clt->paths_up); 2143 if (--clt->paths_up == 0) 2144 clt->link_ev(clt->priv, RTRS_CLT_LINK_EV_DISCONNECTED); 2145 mutex_unlock(&clt->paths_ev_mutex); 2146 } 2147 2148 static void rtrs_clt_stop_and_destroy_conns(struct rtrs_clt_path *clt_path) 2149 { 2150 struct rtrs_clt_con *con; 2151 unsigned int cid; 2152 2153 WARN_ON(READ_ONCE(clt_path->state) == RTRS_CLT_CONNECTED); 2154 2155 /* 2156 * Possible race with rtrs_clt_open(), when DEVICE_REMOVAL comes 2157 * exactly in between. Start destroying after it finishes. 2158 */ 2159 mutex_lock(&clt_path->init_mutex); 2160 mutex_unlock(&clt_path->init_mutex); 2161 2162 /* 2163 * All IO paths must observe !CONNECTED state before we 2164 * free everything. 2165 */ 2166 synchronize_rcu(); 2167 2168 rtrs_stop_hb(&clt_path->s); 2169 2170 /* 2171 * The order it utterly crucial: firstly disconnect and complete all 2172 * rdma requests with error (thus set in_use=false for requests), 2173 * then fail outstanding requests checking in_use for each, and 2174 * eventually notify upper layer about session disconnection. 2175 */ 2176 2177 for (cid = 0; cid < clt_path->s.con_num; cid++) { 2178 if (!clt_path->s.con[cid]) 2179 break; 2180 con = to_clt_con(clt_path->s.con[cid]); 2181 stop_cm(con); 2182 } 2183 fail_all_outstanding_reqs(clt_path); 2184 free_path_reqs(clt_path); 2185 rtrs_clt_path_down(clt_path); 2186 2187 /* 2188 * Wait for graceful shutdown, namely when peer side invokes 2189 * rdma_disconnect(). 'connected_cnt' is decremented only on 2190 * CM events, thus if other side had crashed and hb has detected 2191 * something is wrong, here we will stuck for exactly timeout ms, 2192 * since CM does not fire anything. That is fine, we are not in 2193 * hurry. 2194 */ 2195 wait_event_timeout(clt_path->state_wq, 2196 !atomic_read(&clt_path->connected_cnt), 2197 msecs_to_jiffies(RTRS_CONNECT_TIMEOUT_MS)); 2198 2199 for (cid = 0; cid < clt_path->s.con_num; cid++) { 2200 if (!clt_path->s.con[cid]) 2201 break; 2202 con = to_clt_con(clt_path->s.con[cid]); 2203 mutex_lock(&con->con_mutex); 2204 destroy_con_cq_qp(con); 2205 mutex_unlock(&con->con_mutex); 2206 destroy_cm(con); 2207 destroy_con(con); 2208 } 2209 } 2210 2211 static void rtrs_clt_remove_path_from_arr(struct rtrs_clt_path *clt_path) 2212 { 2213 struct rtrs_clt_sess *clt = clt_path->clt; 2214 struct rtrs_clt_path *next; 2215 bool wait_for_grace = false; 2216 int cpu; 2217 2218 mutex_lock(&clt->paths_mutex); 2219 list_del_rcu(&clt_path->s.entry); 2220 2221 /* Make sure everybody observes path removal. */ 2222 synchronize_rcu(); 2223 2224 /* 2225 * At this point nobody sees @sess in the list, but still we have 2226 * dangling pointer @pcpu_path which _can_ point to @sess. Since 2227 * nobody can observe @sess in the list, we guarantee that IO path 2228 * will not assign @sess to @pcpu_path, i.e. @pcpu_path can be equal 2229 * to @sess, but can never again become @sess. 2230 */ 2231 2232 /* 2233 * Decrement paths number only after grace period, because 2234 * caller of do_each_path() must firstly observe list without 2235 * path and only then decremented paths number. 2236 * 2237 * Otherwise there can be the following situation: 2238 * o Two paths exist and IO is coming. 2239 * o One path is removed: 2240 * CPU#0 CPU#1 2241 * do_each_path(): rtrs_clt_remove_path_from_arr(): 2242 * path = get_next_path() 2243 * ^^^ list_del_rcu(path) 2244 * [!CONNECTED path] clt->paths_num-- 2245 * ^^^^^^^^^ 2246 * load clt->paths_num from 2 to 1 2247 * ^^^^^^^^^ 2248 * sees 1 2249 * 2250 * path is observed as !CONNECTED, but do_each_path() loop 2251 * ends, because expression i < clt->paths_num is false. 2252 */ 2253 clt->paths_num--; 2254 2255 /* 2256 * Get @next connection from current @sess which is going to be 2257 * removed. If @sess is the last element, then @next is NULL. 2258 */ 2259 rcu_read_lock(); 2260 next = rtrs_clt_get_next_path_or_null(&clt->paths_list, clt_path); 2261 rcu_read_unlock(); 2262 2263 /* 2264 * @pcpu paths can still point to the path which is going to be 2265 * removed, so change the pointer manually. 2266 */ 2267 for_each_possible_cpu(cpu) { 2268 struct rtrs_clt_path __rcu **ppcpu_path; 2269 2270 ppcpu_path = per_cpu_ptr(clt->pcpu_path, cpu); 2271 if (rcu_dereference_protected(*ppcpu_path, 2272 lockdep_is_held(&clt->paths_mutex)) != clt_path) 2273 /* 2274 * synchronize_rcu() was called just after deleting 2275 * entry from the list, thus IO code path cannot 2276 * change pointer back to the pointer which is going 2277 * to be removed, we are safe here. 2278 */ 2279 continue; 2280 2281 /* 2282 * We race with IO code path, which also changes pointer, 2283 * thus we have to be careful not to overwrite it. 2284 */ 2285 if (try_cmpxchg((struct rtrs_clt_path **)ppcpu_path, &clt_path, 2286 next)) 2287 /* 2288 * @ppcpu_path was successfully replaced with @next, 2289 * that means that someone could also pick up the 2290 * @sess and dereferencing it right now, so wait for 2291 * a grace period is required. 2292 */ 2293 wait_for_grace = true; 2294 } 2295 if (wait_for_grace) 2296 synchronize_rcu(); 2297 2298 mutex_unlock(&clt->paths_mutex); 2299 } 2300 2301 static void rtrs_clt_add_path_to_arr(struct rtrs_clt_path *clt_path) 2302 { 2303 struct rtrs_clt_sess *clt = clt_path->clt; 2304 2305 mutex_lock(&clt->paths_mutex); 2306 clt->paths_num++; 2307 2308 list_add_tail_rcu(&clt_path->s.entry, &clt->paths_list); 2309 mutex_unlock(&clt->paths_mutex); 2310 } 2311 2312 static void rtrs_clt_close_work(struct work_struct *work) 2313 { 2314 struct rtrs_clt_path *clt_path; 2315 2316 clt_path = container_of(work, struct rtrs_clt_path, close_work); 2317 2318 cancel_work_sync(&clt_path->err_recovery_work); 2319 cancel_delayed_work_sync(&clt_path->reconnect_dwork); 2320 rtrs_clt_stop_and_destroy_conns(clt_path); 2321 rtrs_clt_change_state_get_old(clt_path, RTRS_CLT_CLOSED, NULL); 2322 } 2323 2324 static int init_conns(struct rtrs_clt_path *clt_path) 2325 { 2326 unsigned int cid; 2327 int err, i; 2328 2329 /* 2330 * On every new session connections increase reconnect counter 2331 * to avoid clashes with previous sessions not yet closed 2332 * sessions on a server side. 2333 */ 2334 clt_path->s.recon_cnt++; 2335 2336 /* Establish all RDMA connections */ 2337 for (cid = 0; cid < clt_path->s.con_num; cid++) { 2338 err = create_con(clt_path, cid); 2339 if (err) 2340 goto destroy; 2341 2342 err = create_cm(to_clt_con(clt_path->s.con[cid])); 2343 if (err) 2344 goto destroy; 2345 } 2346 2347 /* 2348 * Set the cid to con_num - 1, since if we fail later, we want to stay in bounds. 2349 */ 2350 cid = clt_path->s.con_num - 1; 2351 2352 err = alloc_path_reqs(clt_path); 2353 if (err) 2354 goto destroy; 2355 2356 return 0; 2357 2358 destroy: 2359 /* Make sure we do the cleanup in the order they are created */ 2360 for (i = 0; i <= cid; i++) { 2361 struct rtrs_clt_con *con; 2362 2363 if (!clt_path->s.con[i]) 2364 break; 2365 2366 con = to_clt_con(clt_path->s.con[i]); 2367 if (con->c.cm_id) { 2368 stop_cm(con); 2369 mutex_lock(&con->con_mutex); 2370 destroy_con_cq_qp(con); 2371 mutex_unlock(&con->con_mutex); 2372 destroy_cm(con); 2373 } 2374 destroy_con(con); 2375 } 2376 /* 2377 * If we've never taken async path and got an error, say, 2378 * doing rdma_resolve_addr(), switch to CONNECTION_ERR state 2379 * manually to keep reconnecting. 2380 */ 2381 rtrs_clt_change_state_get_old(clt_path, RTRS_CLT_CONNECTING_ERR, NULL); 2382 2383 return err; 2384 } 2385 2386 static void rtrs_clt_info_req_done(struct ib_cq *cq, struct ib_wc *wc) 2387 { 2388 struct rtrs_clt_con *con = to_clt_con(wc->qp->qp_context); 2389 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 2390 struct rtrs_iu *iu; 2391 2392 iu = container_of(wc->wr_cqe, struct rtrs_iu, cqe); 2393 rtrs_iu_free(iu, clt_path->s.dev->ib_dev, 1); 2394 2395 if (wc->status != IB_WC_SUCCESS) { 2396 rtrs_err(clt_path->clt, "Path info request send failed: %s\n", 2397 ib_wc_status_msg(wc->status)); 2398 rtrs_clt_change_state_get_old(clt_path, RTRS_CLT_CONNECTING_ERR, NULL); 2399 return; 2400 } 2401 2402 rtrs_clt_update_wc_stats(con); 2403 } 2404 2405 static int process_info_rsp(struct rtrs_clt_path *clt_path, 2406 const struct rtrs_msg_info_rsp *msg) 2407 { 2408 unsigned int sg_cnt, total_len; 2409 int i, sgi; 2410 2411 sg_cnt = le16_to_cpu(msg->sg_cnt); 2412 if (!sg_cnt || (clt_path->queue_depth % sg_cnt)) { 2413 rtrs_err(clt_path->clt, 2414 "Incorrect sg_cnt %d, is not multiple\n", 2415 sg_cnt); 2416 return -EINVAL; 2417 } 2418 2419 /* 2420 * Check if IB immediate data size is enough to hold the mem_id and 2421 * the offset inside the memory chunk. 2422 */ 2423 if ((ilog2(sg_cnt - 1) + 1) + (ilog2(clt_path->chunk_size - 1) + 1) > 2424 MAX_IMM_PAYL_BITS) { 2425 rtrs_err(clt_path->clt, 2426 "RDMA immediate size (%db) not enough to encode %d buffers of size %dB\n", 2427 MAX_IMM_PAYL_BITS, sg_cnt, clt_path->chunk_size); 2428 return -EINVAL; 2429 } 2430 total_len = 0; 2431 for (sgi = 0, i = 0; sgi < sg_cnt && i < clt_path->queue_depth; sgi++) { 2432 const struct rtrs_sg_desc *desc = &msg->desc[sgi]; 2433 u32 len, rkey; 2434 u64 addr; 2435 2436 addr = le64_to_cpu(desc->addr); 2437 rkey = le32_to_cpu(desc->key); 2438 len = le32_to_cpu(desc->len); 2439 2440 total_len += len; 2441 2442 if (!len || (len % clt_path->chunk_size)) { 2443 rtrs_err(clt_path->clt, "Incorrect [%d].len %d\n", 2444 sgi, 2445 len); 2446 return -EINVAL; 2447 } 2448 for ( ; len && i < clt_path->queue_depth; i++) { 2449 clt_path->rbufs[i].addr = addr; 2450 clt_path->rbufs[i].rkey = rkey; 2451 2452 len -= clt_path->chunk_size; 2453 addr += clt_path->chunk_size; 2454 } 2455 } 2456 /* Sanity check */ 2457 if (sgi != sg_cnt || i != clt_path->queue_depth) { 2458 rtrs_err(clt_path->clt, 2459 "Incorrect sg vector, not fully mapped\n"); 2460 return -EINVAL; 2461 } 2462 if (total_len != clt_path->chunk_size * clt_path->queue_depth) { 2463 rtrs_err(clt_path->clt, "Incorrect total_len %d\n", total_len); 2464 return -EINVAL; 2465 } 2466 2467 return 0; 2468 } 2469 2470 static void rtrs_clt_info_rsp_done(struct ib_cq *cq, struct ib_wc *wc) 2471 { 2472 struct rtrs_clt_con *con = to_clt_con(wc->qp->qp_context); 2473 struct rtrs_clt_path *clt_path = to_clt_path(con->c.path); 2474 struct rtrs_msg_info_rsp *msg; 2475 enum rtrs_clt_state state; 2476 struct rtrs_iu *iu; 2477 size_t rx_sz; 2478 int err; 2479 2480 state = RTRS_CLT_CONNECTING_ERR; 2481 2482 WARN_ON(con->c.cid); 2483 iu = container_of(wc->wr_cqe, struct rtrs_iu, cqe); 2484 if (wc->status != IB_WC_SUCCESS) { 2485 rtrs_err(clt_path->clt, "Path info response recv failed: %s\n", 2486 ib_wc_status_msg(wc->status)); 2487 goto out; 2488 } 2489 WARN_ON(wc->opcode != IB_WC_RECV); 2490 2491 if (wc->byte_len < sizeof(*msg)) { 2492 rtrs_err(clt_path->clt, "Path info response is malformed: size %d\n", 2493 wc->byte_len); 2494 goto out; 2495 } 2496 ib_dma_sync_single_for_cpu(clt_path->s.dev->ib_dev, iu->dma_addr, 2497 iu->size, DMA_FROM_DEVICE); 2498 msg = iu->buf; 2499 if (le16_to_cpu(msg->type) != RTRS_MSG_INFO_RSP) { 2500 rtrs_err(clt_path->clt, "Path info response is malformed: type %d\n", 2501 le16_to_cpu(msg->type)); 2502 goto out; 2503 } 2504 rx_sz = sizeof(*msg); 2505 rx_sz += sizeof(msg->desc[0]) * le16_to_cpu(msg->sg_cnt); 2506 if (wc->byte_len < rx_sz) { 2507 rtrs_err(clt_path->clt, "Path info response is malformed: size %d\n", 2508 wc->byte_len); 2509 goto out; 2510 } 2511 err = process_info_rsp(clt_path, msg); 2512 if (err) 2513 goto out; 2514 2515 err = post_recv_path(clt_path); 2516 if (err) 2517 goto out; 2518 2519 state = RTRS_CLT_CONNECTED; 2520 2521 out: 2522 rtrs_clt_update_wc_stats(con); 2523 rtrs_iu_free(iu, clt_path->s.dev->ib_dev, 1); 2524 rtrs_clt_change_state_get_old(clt_path, state, NULL); 2525 } 2526 2527 static int rtrs_send_path_info(struct rtrs_clt_path *clt_path) 2528 { 2529 struct rtrs_clt_con *usr_con = to_clt_con(clt_path->s.con[0]); 2530 struct rtrs_msg_info_req *msg; 2531 struct rtrs_iu *tx_iu, *rx_iu; 2532 size_t rx_sz; 2533 int err; 2534 2535 rx_sz = sizeof(struct rtrs_msg_info_rsp); 2536 rx_sz += sizeof(struct rtrs_sg_desc) * clt_path->queue_depth; 2537 2538 tx_iu = rtrs_iu_alloc(1, sizeof(struct rtrs_msg_info_req), GFP_KERNEL, 2539 clt_path->s.dev->ib_dev, DMA_TO_DEVICE, 2540 rtrs_clt_info_req_done); 2541 rx_iu = rtrs_iu_alloc(1, rx_sz, GFP_KERNEL, clt_path->s.dev->ib_dev, 2542 DMA_FROM_DEVICE, rtrs_clt_info_rsp_done); 2543 if (!tx_iu || !rx_iu) { 2544 err = -ENOMEM; 2545 goto out; 2546 } 2547 /* Prepare for getting info response */ 2548 err = rtrs_iu_post_recv(&usr_con->c, rx_iu); 2549 if (err) { 2550 rtrs_err(clt_path->clt, "rtrs_iu_post_recv(), err: %d\n", err); 2551 goto out; 2552 } 2553 rx_iu = NULL; 2554 2555 msg = tx_iu->buf; 2556 msg->type = cpu_to_le16(RTRS_MSG_INFO_REQ); 2557 memcpy(msg->pathname, clt_path->s.sessname, sizeof(msg->pathname)); 2558 2559 ib_dma_sync_single_for_device(clt_path->s.dev->ib_dev, 2560 tx_iu->dma_addr, 2561 tx_iu->size, DMA_TO_DEVICE); 2562 2563 /* Send info request */ 2564 err = rtrs_iu_post_send(&usr_con->c, tx_iu, sizeof(*msg), NULL); 2565 if (err) { 2566 rtrs_err(clt_path->clt, "rtrs_iu_post_send(), err: %d\n", err); 2567 goto out; 2568 } 2569 tx_iu = NULL; 2570 2571 /* Wait for state change */ 2572 wait_event_interruptible_timeout(clt_path->state_wq, 2573 clt_path->state != RTRS_CLT_CONNECTING, 2574 msecs_to_jiffies( 2575 RTRS_CONNECT_TIMEOUT_MS)); 2576 if (READ_ONCE(clt_path->state) != RTRS_CLT_CONNECTED) { 2577 if (READ_ONCE(clt_path->state) == RTRS_CLT_CONNECTING_ERR) 2578 err = -ECONNRESET; 2579 else 2580 err = -ETIMEDOUT; 2581 } 2582 2583 out: 2584 if (tx_iu) 2585 rtrs_iu_free(tx_iu, clt_path->s.dev->ib_dev, 1); 2586 if (rx_iu) 2587 rtrs_iu_free(rx_iu, clt_path->s.dev->ib_dev, 1); 2588 if (err) 2589 /* If we've never taken async path because of malloc problems */ 2590 rtrs_clt_change_state_get_old(clt_path, 2591 RTRS_CLT_CONNECTING_ERR, NULL); 2592 2593 return err; 2594 } 2595 2596 /** 2597 * init_path() - establishes all path connections and does handshake 2598 * @clt_path: client path. 2599 * In case of error full close or reconnect procedure should be taken, 2600 * because reconnect or close async works can be started. 2601 */ 2602 static int init_path(struct rtrs_clt_path *clt_path) 2603 { 2604 int err; 2605 char str[NAME_MAX]; 2606 struct rtrs_addr path = { 2607 .src = &clt_path->s.src_addr, 2608 .dst = &clt_path->s.dst_addr, 2609 }; 2610 2611 rtrs_addr_to_str(&path, str, sizeof(str)); 2612 2613 mutex_lock(&clt_path->init_mutex); 2614 err = init_conns(clt_path); 2615 if (err) { 2616 rtrs_err(clt_path->clt, 2617 "init_conns() failed: err=%d path=%s [%s:%u]\n", err, 2618 str, clt_path->hca_name, clt_path->hca_port); 2619 goto out; 2620 } 2621 err = rtrs_send_path_info(clt_path); 2622 if (err) { 2623 rtrs_err(clt_path->clt, 2624 "rtrs_send_path_info() failed: err=%d path=%s [%s:%u]\n", 2625 err, str, clt_path->hca_name, clt_path->hca_port); 2626 goto out; 2627 } 2628 rtrs_clt_path_up(clt_path); 2629 rtrs_start_hb(&clt_path->s); 2630 out: 2631 mutex_unlock(&clt_path->init_mutex); 2632 2633 return err; 2634 } 2635 2636 static void rtrs_clt_reconnect_work(struct work_struct *work) 2637 { 2638 struct rtrs_clt_path *clt_path; 2639 struct rtrs_clt_sess *clt; 2640 int err; 2641 2642 clt_path = container_of(to_delayed_work(work), struct rtrs_clt_path, 2643 reconnect_dwork); 2644 clt = clt_path->clt; 2645 2646 trace_rtrs_clt_reconnect_work(clt_path); 2647 2648 if (READ_ONCE(clt_path->state) != RTRS_CLT_RECONNECTING) 2649 return; 2650 2651 if (clt_path->reconnect_attempts >= clt->max_reconnect_attempts) { 2652 /* Close a path completely if max attempts is reached */ 2653 rtrs_clt_close_conns(clt_path, false); 2654 return; 2655 } 2656 clt_path->reconnect_attempts++; 2657 2658 msleep(RTRS_RECONNECT_BACKOFF); 2659 if (rtrs_clt_change_state_get_old(clt_path, RTRS_CLT_CONNECTING, NULL)) { 2660 err = init_path(clt_path); 2661 if (err) 2662 goto reconnect_again; 2663 } 2664 2665 return; 2666 2667 reconnect_again: 2668 if (rtrs_clt_change_state_get_old(clt_path, RTRS_CLT_RECONNECTING, NULL)) { 2669 clt_path->stats->reconnects.fail_cnt++; 2670 queue_work(rtrs_wq, &clt_path->err_recovery_work); 2671 } 2672 } 2673 2674 static void rtrs_clt_dev_release(struct device *dev) 2675 { 2676 struct rtrs_clt_sess *clt = container_of(dev, struct rtrs_clt_sess, 2677 dev); 2678 2679 mutex_destroy(&clt->paths_ev_mutex); 2680 mutex_destroy(&clt->paths_mutex); 2681 kfree(clt); 2682 } 2683 2684 static struct rtrs_clt_sess *alloc_clt(const char *sessname, size_t paths_num, 2685 u16 port, size_t pdu_sz, void *priv, 2686 void (*link_ev)(void *priv, 2687 enum rtrs_clt_link_ev ev), 2688 unsigned int reconnect_delay_sec, 2689 unsigned int max_reconnect_attempts) 2690 { 2691 struct rtrs_clt_sess *clt; 2692 int err; 2693 2694 if (!paths_num || paths_num > MAX_PATHS_NUM) 2695 return ERR_PTR(-EINVAL); 2696 2697 if (strlen(sessname) >= sizeof(clt->sessname)) 2698 return ERR_PTR(-EINVAL); 2699 2700 clt = kzalloc(sizeof(*clt), GFP_KERNEL); 2701 if (!clt) 2702 return ERR_PTR(-ENOMEM); 2703 2704 clt->pcpu_path = alloc_percpu(typeof(*clt->pcpu_path)); 2705 if (!clt->pcpu_path) { 2706 kfree(clt); 2707 return ERR_PTR(-ENOMEM); 2708 } 2709 2710 clt->dev.class = &rtrs_clt_dev_class; 2711 clt->dev.release = rtrs_clt_dev_release; 2712 uuid_gen(&clt->paths_uuid); 2713 INIT_LIST_HEAD_RCU(&clt->paths_list); 2714 clt->paths_num = paths_num; 2715 clt->paths_up = MAX_PATHS_NUM; 2716 clt->port = port; 2717 clt->pdu_sz = pdu_sz; 2718 clt->max_segments = RTRS_MAX_SEGMENTS; 2719 clt->reconnect_delay_sec = reconnect_delay_sec; 2720 clt->max_reconnect_attempts = max_reconnect_attempts; 2721 clt->priv = priv; 2722 clt->link_ev = link_ev; 2723 clt->mp_policy = MP_POLICY_MIN_INFLIGHT; 2724 strscpy(clt->sessname, sessname, sizeof(clt->sessname)); 2725 init_waitqueue_head(&clt->permits_wait); 2726 mutex_init(&clt->paths_ev_mutex); 2727 mutex_init(&clt->paths_mutex); 2728 device_initialize(&clt->dev); 2729 2730 err = dev_set_name(&clt->dev, "%s", sessname); 2731 if (err) 2732 goto err_put; 2733 2734 /* 2735 * Suppress user space notification until 2736 * sysfs files are created 2737 */ 2738 dev_set_uevent_suppress(&clt->dev, true); 2739 err = device_add(&clt->dev); 2740 if (err) 2741 goto err_put; 2742 2743 clt->kobj_paths = kobject_create_and_add("paths", &clt->dev.kobj); 2744 if (!clt->kobj_paths) { 2745 err = -ENOMEM; 2746 goto err_del; 2747 } 2748 err = rtrs_clt_create_sysfs_root_files(clt); 2749 if (err) { 2750 kobject_del(clt->kobj_paths); 2751 kobject_put(clt->kobj_paths); 2752 goto err_del; 2753 } 2754 dev_set_uevent_suppress(&clt->dev, false); 2755 kobject_uevent(&clt->dev.kobj, KOBJ_ADD); 2756 2757 return clt; 2758 err_del: 2759 device_del(&clt->dev); 2760 err_put: 2761 free_percpu(clt->pcpu_path); 2762 put_device(&clt->dev); 2763 return ERR_PTR(err); 2764 } 2765 2766 static void free_clt(struct rtrs_clt_sess *clt) 2767 { 2768 free_percpu(clt->pcpu_path); 2769 2770 /* 2771 * release callback will free clt and destroy mutexes in last put 2772 */ 2773 device_unregister(&clt->dev); 2774 } 2775 2776 /** 2777 * rtrs_clt_open() - Open a path to an RTRS server 2778 * @ops: holds the link event callback and the private pointer. 2779 * @pathname: name of the path to an RTRS server 2780 * @paths: Paths to be established defined by their src and dst addresses 2781 * @paths_num: Number of elements in the @paths array 2782 * @port: port to be used by the RTRS session 2783 * @pdu_sz: Size of extra payload which can be accessed after permit allocation. 2784 * @reconnect_delay_sec: time between reconnect tries 2785 * @max_reconnect_attempts: Number of times to reconnect on error before giving 2786 * up, 0 for * disabled, -1 for forever 2787 * @nr_poll_queues: number of polling mode connection using IB_POLL_DIRECT flag 2788 * 2789 * Starts session establishment with the rtrs_server. The function can block 2790 * up to ~2000ms before it returns. 2791 * 2792 * Return a valid pointer on success otherwise PTR_ERR. 2793 */ 2794 struct rtrs_clt_sess *rtrs_clt_open(struct rtrs_clt_ops *ops, 2795 const char *pathname, 2796 const struct rtrs_addr *paths, 2797 size_t paths_num, u16 port, 2798 size_t pdu_sz, u8 reconnect_delay_sec, 2799 s16 max_reconnect_attempts, u32 nr_poll_queues) 2800 { 2801 struct rtrs_clt_path *clt_path, *tmp; 2802 struct rtrs_clt_sess *clt; 2803 int err, i; 2804 2805 if (strchr(pathname, '/') || strchr(pathname, '.')) { 2806 pr_err("pathname cannot contain / and .\n"); 2807 err = -EINVAL; 2808 goto out; 2809 } 2810 2811 clt = alloc_clt(pathname, paths_num, port, pdu_sz, ops->priv, 2812 ops->link_ev, 2813 reconnect_delay_sec, 2814 max_reconnect_attempts); 2815 if (IS_ERR(clt)) { 2816 err = PTR_ERR(clt); 2817 goto out; 2818 } 2819 for (i = 0; i < paths_num; i++) { 2820 struct rtrs_clt_path *clt_path; 2821 2822 clt_path = alloc_path(clt, &paths[i], nr_cpu_ids, 2823 nr_poll_queues); 2824 if (IS_ERR(clt_path)) { 2825 err = PTR_ERR(clt_path); 2826 goto close_all_path; 2827 } 2828 if (!i) 2829 clt_path->for_new_clt = 1; 2830 list_add_tail_rcu(&clt_path->s.entry, &clt->paths_list); 2831 2832 err = init_path(clt_path); 2833 if (err) { 2834 list_del_rcu(&clt_path->s.entry); 2835 rtrs_clt_close_conns(clt_path, true); 2836 free_percpu(clt_path->stats->pcpu_stats); 2837 kfree(clt_path->stats); 2838 free_path(clt_path); 2839 goto close_all_path; 2840 } 2841 2842 err = rtrs_clt_create_path_files(clt_path); 2843 if (err) { 2844 list_del_rcu(&clt_path->s.entry); 2845 rtrs_clt_close_conns(clt_path, true); 2846 free_percpu(clt_path->stats->pcpu_stats); 2847 kfree(clt_path->stats); 2848 free_path(clt_path); 2849 goto close_all_path; 2850 } 2851 } 2852 err = alloc_permits(clt); 2853 if (err) 2854 goto close_all_path; 2855 2856 return clt; 2857 2858 close_all_path: 2859 list_for_each_entry_safe(clt_path, tmp, &clt->paths_list, s.entry) { 2860 rtrs_clt_destroy_path_files(clt_path, NULL); 2861 rtrs_clt_close_conns(clt_path, true); 2862 kobject_put(&clt_path->kobj); 2863 } 2864 rtrs_clt_destroy_sysfs_root(clt); 2865 free_clt(clt); 2866 2867 out: 2868 return ERR_PTR(err); 2869 } 2870 EXPORT_SYMBOL(rtrs_clt_open); 2871 2872 /** 2873 * rtrs_clt_close() - Close a path 2874 * @clt: Session handle. Session is freed upon return. 2875 */ 2876 void rtrs_clt_close(struct rtrs_clt_sess *clt) 2877 { 2878 struct rtrs_clt_path *clt_path, *tmp; 2879 2880 /* Firstly forbid sysfs access */ 2881 rtrs_clt_destroy_sysfs_root(clt); 2882 2883 /* Now it is safe to iterate over all paths without locks */ 2884 list_for_each_entry_safe(clt_path, tmp, &clt->paths_list, s.entry) { 2885 rtrs_clt_close_conns(clt_path, true); 2886 rtrs_clt_destroy_path_files(clt_path, NULL); 2887 kobject_put(&clt_path->kobj); 2888 } 2889 free_permits(clt); 2890 free_clt(clt); 2891 } 2892 EXPORT_SYMBOL(rtrs_clt_close); 2893 2894 int rtrs_clt_reconnect_from_sysfs(struct rtrs_clt_path *clt_path) 2895 { 2896 enum rtrs_clt_state old_state; 2897 int err = -EBUSY; 2898 bool changed; 2899 2900 changed = rtrs_clt_change_state_get_old(clt_path, 2901 RTRS_CLT_RECONNECTING, 2902 &old_state); 2903 if (changed) { 2904 clt_path->reconnect_attempts = 0; 2905 rtrs_clt_stop_and_destroy_conns(clt_path); 2906 queue_delayed_work(rtrs_wq, &clt_path->reconnect_dwork, 0); 2907 } 2908 if (changed || old_state == RTRS_CLT_RECONNECTING) { 2909 /* 2910 * flush_delayed_work() queues pending work for immediate 2911 * execution, so do the flush if we have queued something 2912 * right now or work is pending. 2913 */ 2914 flush_delayed_work(&clt_path->reconnect_dwork); 2915 err = (READ_ONCE(clt_path->state) == 2916 RTRS_CLT_CONNECTED ? 0 : -ENOTCONN); 2917 } 2918 2919 return err; 2920 } 2921 2922 int rtrs_clt_remove_path_from_sysfs(struct rtrs_clt_path *clt_path, 2923 const struct attribute *sysfs_self) 2924 { 2925 enum rtrs_clt_state old_state; 2926 bool changed; 2927 2928 /* 2929 * Continue stopping path till state was changed to DEAD or 2930 * state was observed as DEAD: 2931 * 1. State was changed to DEAD - we were fast and nobody 2932 * invoked rtrs_clt_reconnect(), which can again start 2933 * reconnecting. 2934 * 2. State was observed as DEAD - we have someone in parallel 2935 * removing the path. 2936 */ 2937 do { 2938 rtrs_clt_close_conns(clt_path, true); 2939 changed = rtrs_clt_change_state_get_old(clt_path, 2940 RTRS_CLT_DEAD, 2941 &old_state); 2942 } while (!changed && old_state != RTRS_CLT_DEAD); 2943 2944 if (changed) { 2945 rtrs_clt_remove_path_from_arr(clt_path); 2946 rtrs_clt_destroy_path_files(clt_path, sysfs_self); 2947 kobject_put(&clt_path->kobj); 2948 } 2949 2950 return 0; 2951 } 2952 2953 void rtrs_clt_set_max_reconnect_attempts(struct rtrs_clt_sess *clt, int value) 2954 { 2955 clt->max_reconnect_attempts = (unsigned int)value; 2956 } 2957 2958 int rtrs_clt_get_max_reconnect_attempts(const struct rtrs_clt_sess *clt) 2959 { 2960 return (int)clt->max_reconnect_attempts; 2961 } 2962 2963 /** 2964 * rtrs_clt_request() - Request data transfer to/from server via RDMA. 2965 * 2966 * @dir: READ/WRITE 2967 * @ops: callback function to be called as confirmation, and the pointer. 2968 * @clt: Session 2969 * @permit: Preallocated permit 2970 * @vec: Message that is sent to server together with the request. 2971 * Sum of len of all @vec elements limited to <= IO_MSG_SIZE. 2972 * Since the msg is copied internally it can be allocated on stack. 2973 * @nr: Number of elements in @vec. 2974 * @data_len: length of data sent to/from server 2975 * @sg: Pages to be sent/received to/from server. 2976 * @sg_cnt: Number of elements in the @sg 2977 * 2978 * Return: 2979 * 0: Success 2980 * <0: Error 2981 * 2982 * On dir=READ rtrs client will request a data transfer from Server to client. 2983 * The data that the server will respond with will be stored in @sg when 2984 * the user receives an %RTRS_CLT_RDMA_EV_RDMA_REQUEST_WRITE_COMPL event. 2985 * On dir=WRITE rtrs client will rdma write data in sg to server side. 2986 */ 2987 int rtrs_clt_request(int dir, struct rtrs_clt_req_ops *ops, 2988 struct rtrs_clt_sess *clt, struct rtrs_permit *permit, 2989 const struct kvec *vec, size_t nr, size_t data_len, 2990 struct scatterlist *sg, unsigned int sg_cnt) 2991 { 2992 struct rtrs_clt_io_req *req; 2993 struct rtrs_clt_path *clt_path; 2994 2995 enum dma_data_direction dma_dir; 2996 int err = -ECONNABORTED, i; 2997 size_t usr_len, hdr_len; 2998 struct path_it it; 2999 3000 /* Get kvec length */ 3001 for (i = 0, usr_len = 0; i < nr; i++) 3002 usr_len += vec[i].iov_len; 3003 3004 if (dir == READ) { 3005 hdr_len = sizeof(struct rtrs_msg_rdma_read) + 3006 sg_cnt * sizeof(struct rtrs_sg_desc); 3007 dma_dir = DMA_FROM_DEVICE; 3008 } else { 3009 hdr_len = sizeof(struct rtrs_msg_rdma_write); 3010 dma_dir = DMA_TO_DEVICE; 3011 } 3012 3013 rcu_read_lock(); 3014 for (path_it_init(&it, clt); 3015 (clt_path = it.next_path(&it)) && it.i < it.clt->paths_num; it.i++) { 3016 if (READ_ONCE(clt_path->state) != RTRS_CLT_CONNECTED) 3017 continue; 3018 3019 if (usr_len + hdr_len > clt_path->max_hdr_size) { 3020 rtrs_wrn_rl(clt_path->clt, 3021 "%s request failed, user message size is %zu and header length %zu, but max size is %u\n", 3022 dir == READ ? "Read" : "Write", 3023 usr_len, hdr_len, clt_path->max_hdr_size); 3024 err = -EMSGSIZE; 3025 break; 3026 } 3027 req = rtrs_clt_get_req(clt_path, ops->conf_fn, permit, ops->priv, 3028 vec, usr_len, sg, sg_cnt, data_len, 3029 dma_dir); 3030 if (dir == READ) 3031 err = rtrs_clt_read_req(req); 3032 else 3033 err = rtrs_clt_write_req(req); 3034 if (err) { 3035 req->in_use = false; 3036 continue; 3037 } 3038 /* Success path */ 3039 break; 3040 } 3041 path_it_deinit(&it); 3042 rcu_read_unlock(); 3043 3044 return err; 3045 } 3046 EXPORT_SYMBOL(rtrs_clt_request); 3047 3048 int rtrs_clt_rdma_cq_direct(struct rtrs_clt_sess *clt, unsigned int index) 3049 { 3050 /* If no path, return -1 for block layer not to try again */ 3051 int cnt = -1; 3052 struct rtrs_con *con; 3053 struct rtrs_clt_path *clt_path; 3054 struct path_it it; 3055 3056 rcu_read_lock(); 3057 for (path_it_init(&it, clt); 3058 (clt_path = it.next_path(&it)) && it.i < it.clt->paths_num; it.i++) { 3059 if (READ_ONCE(clt_path->state) != RTRS_CLT_CONNECTED) 3060 continue; 3061 3062 con = clt_path->s.con[index + 1]; 3063 cnt = ib_process_cq_direct(con->cq, -1); 3064 if (cnt) 3065 break; 3066 } 3067 path_it_deinit(&it); 3068 rcu_read_unlock(); 3069 3070 return cnt; 3071 } 3072 EXPORT_SYMBOL(rtrs_clt_rdma_cq_direct); 3073 3074 /** 3075 * rtrs_clt_query() - queries RTRS session attributes 3076 *@clt: session pointer 3077 *@attr: query results for session attributes. 3078 * Returns: 3079 * 0 on success 3080 * -ECOMM no connection to the server 3081 */ 3082 int rtrs_clt_query(struct rtrs_clt_sess *clt, struct rtrs_attrs *attr) 3083 { 3084 if (!rtrs_clt_is_connected(clt)) 3085 return -ECOMM; 3086 3087 attr->queue_depth = clt->queue_depth; 3088 attr->max_segments = clt->max_segments; 3089 /* Cap max_io_size to min of remote buffer size and the fr pages */ 3090 attr->max_io_size = min_t(int, clt->max_io_size, 3091 clt->max_segments * SZ_4K); 3092 3093 return 0; 3094 } 3095 EXPORT_SYMBOL(rtrs_clt_query); 3096 3097 int rtrs_clt_create_path_from_sysfs(struct rtrs_clt_sess *clt, 3098 struct rtrs_addr *addr) 3099 { 3100 struct rtrs_clt_path *clt_path; 3101 int err; 3102 3103 clt_path = alloc_path(clt, addr, nr_cpu_ids, 0); 3104 if (IS_ERR(clt_path)) 3105 return PTR_ERR(clt_path); 3106 3107 mutex_lock(&clt->paths_mutex); 3108 if (clt->paths_num == 0) { 3109 /* 3110 * When all the paths are removed for a session, 3111 * the addition of the first path is like a new session for 3112 * the storage server 3113 */ 3114 clt_path->for_new_clt = 1; 3115 } 3116 3117 mutex_unlock(&clt->paths_mutex); 3118 3119 /* 3120 * It is totally safe to add path in CONNECTING state: coming 3121 * IO will never grab it. Also it is very important to add 3122 * path before init, since init fires LINK_CONNECTED event. 3123 */ 3124 rtrs_clt_add_path_to_arr(clt_path); 3125 3126 err = init_path(clt_path); 3127 if (err) 3128 goto close_path; 3129 3130 err = rtrs_clt_create_path_files(clt_path); 3131 if (err) 3132 goto close_path; 3133 3134 return 0; 3135 3136 close_path: 3137 rtrs_clt_remove_path_from_arr(clt_path); 3138 rtrs_clt_close_conns(clt_path, true); 3139 free_percpu(clt_path->stats->pcpu_stats); 3140 kfree(clt_path->stats); 3141 free_path(clt_path); 3142 3143 return err; 3144 } 3145 3146 void rtrs_clt_ib_event_handler(struct ib_event_handler *handler, 3147 struct ib_event *ibevent) 3148 { 3149 pr_info("Handling event: %s (%d).\n", ib_event_msg(ibevent->event), 3150 ibevent->event); 3151 } 3152 3153 3154 static int rtrs_clt_ib_dev_init(struct rtrs_ib_dev *dev) 3155 { 3156 INIT_IB_EVENT_HANDLER(&dev->event_handler, dev->ib_dev, 3157 rtrs_clt_ib_event_handler); 3158 ib_register_event_handler(&dev->event_handler); 3159 3160 if (!(dev->ib_dev->attrs.device_cap_flags & 3161 IB_DEVICE_MEM_MGT_EXTENSIONS)) { 3162 pr_err("Memory registrations not supported.\n"); 3163 return -ENOTSUPP; 3164 } 3165 3166 return 0; 3167 } 3168 3169 static void rtrs_clt_ib_dev_deinit(struct rtrs_ib_dev *dev) 3170 { 3171 ib_unregister_event_handler(&dev->event_handler); 3172 } 3173 3174 3175 static const struct rtrs_rdma_dev_pd_ops dev_pd_ops = { 3176 .init = rtrs_clt_ib_dev_init, 3177 .deinit = rtrs_clt_ib_dev_deinit 3178 }; 3179 3180 static int __init rtrs_client_init(void) 3181 { 3182 int ret = 0; 3183 3184 rtrs_rdma_dev_pd_init(0, &dev_pd); 3185 ret = class_register(&rtrs_clt_dev_class); 3186 if (ret) { 3187 pr_err("Failed to create rtrs-client dev class\n"); 3188 return ret; 3189 } 3190 rtrs_wq = alloc_workqueue("rtrs_client_wq", 0, 0); 3191 if (!rtrs_wq) { 3192 class_unregister(&rtrs_clt_dev_class); 3193 return -ENOMEM; 3194 } 3195 3196 return 0; 3197 } 3198 3199 static void __exit rtrs_client_exit(void) 3200 { 3201 destroy_workqueue(rtrs_wq); 3202 class_unregister(&rtrs_clt_dev_class); 3203 rtrs_rdma_dev_pd_deinit(&dev_pd); 3204 } 3205 3206 module_init(rtrs_client_init); 3207 module_exit(rtrs_client_exit); 3208