1 // SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB 2 /* 3 * Copyright (c) 2016 Mellanox Technologies Ltd. All rights reserved. 4 * Copyright (c) 2015 System Fabric Works, Inc. All rights reserved. 5 */ 6 7 #include <linux/skbuff.h> 8 9 #include "rxe.h" 10 #include "rxe_loc.h" 11 #include "rxe_queue.h" 12 #include "rxe_task.h" 13 14 enum comp_state { 15 COMPST_GET_ACK, 16 COMPST_GET_WQE, 17 COMPST_COMP_WQE, 18 COMPST_COMP_ACK, 19 COMPST_CHECK_PSN, 20 COMPST_CHECK_ACK, 21 COMPST_READ, 22 COMPST_ATOMIC, 23 COMPST_WRITE_SEND, 24 COMPST_UPDATE_COMP, 25 COMPST_ERROR_RETRY, 26 COMPST_RNR_RETRY, 27 COMPST_ERROR, 28 COMPST_EXIT, /* We have an issue, and we want to rerun the completer */ 29 COMPST_DONE, /* The completer finished successflly */ 30 }; 31 32 static char *comp_state_name[] = { 33 [COMPST_GET_ACK] = "GET ACK", 34 [COMPST_GET_WQE] = "GET WQE", 35 [COMPST_COMP_WQE] = "COMP WQE", 36 [COMPST_COMP_ACK] = "COMP ACK", 37 [COMPST_CHECK_PSN] = "CHECK PSN", 38 [COMPST_CHECK_ACK] = "CHECK ACK", 39 [COMPST_READ] = "READ", 40 [COMPST_ATOMIC] = "ATOMIC", 41 [COMPST_WRITE_SEND] = "WRITE/SEND", 42 [COMPST_UPDATE_COMP] = "UPDATE COMP", 43 [COMPST_ERROR_RETRY] = "ERROR RETRY", 44 [COMPST_RNR_RETRY] = "RNR RETRY", 45 [COMPST_ERROR] = "ERROR", 46 [COMPST_EXIT] = "EXIT", 47 [COMPST_DONE] = "DONE", 48 }; 49 50 static unsigned long rnrnak_usec[32] = { 51 [IB_RNR_TIMER_655_36] = 655360, 52 [IB_RNR_TIMER_000_01] = 10, 53 [IB_RNR_TIMER_000_02] = 20, 54 [IB_RNR_TIMER_000_03] = 30, 55 [IB_RNR_TIMER_000_04] = 40, 56 [IB_RNR_TIMER_000_06] = 60, 57 [IB_RNR_TIMER_000_08] = 80, 58 [IB_RNR_TIMER_000_12] = 120, 59 [IB_RNR_TIMER_000_16] = 160, 60 [IB_RNR_TIMER_000_24] = 240, 61 [IB_RNR_TIMER_000_32] = 320, 62 [IB_RNR_TIMER_000_48] = 480, 63 [IB_RNR_TIMER_000_64] = 640, 64 [IB_RNR_TIMER_000_96] = 960, 65 [IB_RNR_TIMER_001_28] = 1280, 66 [IB_RNR_TIMER_001_92] = 1920, 67 [IB_RNR_TIMER_002_56] = 2560, 68 [IB_RNR_TIMER_003_84] = 3840, 69 [IB_RNR_TIMER_005_12] = 5120, 70 [IB_RNR_TIMER_007_68] = 7680, 71 [IB_RNR_TIMER_010_24] = 10240, 72 [IB_RNR_TIMER_015_36] = 15360, 73 [IB_RNR_TIMER_020_48] = 20480, 74 [IB_RNR_TIMER_030_72] = 30720, 75 [IB_RNR_TIMER_040_96] = 40960, 76 [IB_RNR_TIMER_061_44] = 61410, 77 [IB_RNR_TIMER_081_92] = 81920, 78 [IB_RNR_TIMER_122_88] = 122880, 79 [IB_RNR_TIMER_163_84] = 163840, 80 [IB_RNR_TIMER_245_76] = 245760, 81 [IB_RNR_TIMER_327_68] = 327680, 82 [IB_RNR_TIMER_491_52] = 491520, 83 }; 84 85 static inline unsigned long rnrnak_jiffies(u8 timeout) 86 { 87 return max_t(unsigned long, 88 usecs_to_jiffies(rnrnak_usec[timeout]), 1); 89 } 90 91 static enum ib_wc_opcode wr_to_wc_opcode(enum ib_wr_opcode opcode) 92 { 93 switch (opcode) { 94 case IB_WR_RDMA_WRITE: return IB_WC_RDMA_WRITE; 95 case IB_WR_RDMA_WRITE_WITH_IMM: return IB_WC_RDMA_WRITE; 96 case IB_WR_SEND: return IB_WC_SEND; 97 case IB_WR_SEND_WITH_IMM: return IB_WC_SEND; 98 case IB_WR_RDMA_READ: return IB_WC_RDMA_READ; 99 case IB_WR_ATOMIC_CMP_AND_SWP: return IB_WC_COMP_SWAP; 100 case IB_WR_ATOMIC_FETCH_AND_ADD: return IB_WC_FETCH_ADD; 101 case IB_WR_LSO: return IB_WC_LSO; 102 case IB_WR_SEND_WITH_INV: return IB_WC_SEND; 103 case IB_WR_RDMA_READ_WITH_INV: return IB_WC_RDMA_READ; 104 case IB_WR_LOCAL_INV: return IB_WC_LOCAL_INV; 105 case IB_WR_REG_MR: return IB_WC_REG_MR; 106 case IB_WR_BIND_MW: return IB_WC_BIND_MW; 107 108 default: 109 return 0xff; 110 } 111 } 112 113 void retransmit_timer(struct timer_list *t) 114 { 115 struct rxe_qp *qp = from_timer(qp, t, retrans_timer); 116 117 if (qp->valid) { 118 qp->comp.timeout = 1; 119 rxe_run_task(&qp->comp.task, 1); 120 } 121 } 122 123 void rxe_comp_queue_pkt(struct rxe_qp *qp, struct sk_buff *skb) 124 { 125 int must_sched; 126 127 skb_queue_tail(&qp->resp_pkts, skb); 128 129 must_sched = skb_queue_len(&qp->resp_pkts) > 1; 130 if (must_sched != 0) 131 rxe_counter_inc(SKB_TO_PKT(skb)->rxe, RXE_CNT_COMPLETER_SCHED); 132 133 rxe_run_task(&qp->comp.task, must_sched); 134 } 135 136 static inline enum comp_state get_wqe(struct rxe_qp *qp, 137 struct rxe_pkt_info *pkt, 138 struct rxe_send_wqe **wqe_p) 139 { 140 struct rxe_send_wqe *wqe; 141 142 /* we come here whether or not we found a response packet to see if 143 * there are any posted WQEs 144 */ 145 wqe = queue_head(qp->sq.queue, QUEUE_TYPE_FROM_CLIENT); 146 *wqe_p = wqe; 147 148 /* no WQE or requester has not started it yet */ 149 if (!wqe || wqe->state == wqe_state_posted) 150 return pkt ? COMPST_DONE : COMPST_EXIT; 151 152 /* WQE does not require an ack */ 153 if (wqe->state == wqe_state_done) 154 return COMPST_COMP_WQE; 155 156 /* WQE caused an error */ 157 if (wqe->state == wqe_state_error) 158 return COMPST_ERROR; 159 160 /* we have a WQE, if we also have an ack check its PSN */ 161 return pkt ? COMPST_CHECK_PSN : COMPST_EXIT; 162 } 163 164 static inline void reset_retry_counters(struct rxe_qp *qp) 165 { 166 qp->comp.retry_cnt = qp->attr.retry_cnt; 167 qp->comp.rnr_retry = qp->attr.rnr_retry; 168 qp->comp.started_retry = 0; 169 } 170 171 static inline enum comp_state check_psn(struct rxe_qp *qp, 172 struct rxe_pkt_info *pkt, 173 struct rxe_send_wqe *wqe) 174 { 175 s32 diff; 176 177 /* check to see if response is past the oldest WQE. if it is, complete 178 * send/write or error read/atomic 179 */ 180 diff = psn_compare(pkt->psn, wqe->last_psn); 181 if (diff > 0) { 182 if (wqe->state == wqe_state_pending) { 183 if (wqe->mask & WR_ATOMIC_OR_READ_MASK) 184 return COMPST_ERROR_RETRY; 185 186 reset_retry_counters(qp); 187 return COMPST_COMP_WQE; 188 } else { 189 return COMPST_DONE; 190 } 191 } 192 193 /* compare response packet to expected response */ 194 diff = psn_compare(pkt->psn, qp->comp.psn); 195 if (diff < 0) { 196 /* response is most likely a retried packet if it matches an 197 * uncompleted WQE go complete it else ignore it 198 */ 199 if (pkt->psn == wqe->last_psn) 200 return COMPST_COMP_ACK; 201 else 202 return COMPST_DONE; 203 } else if ((diff > 0) && (wqe->mask & WR_ATOMIC_OR_READ_MASK)) { 204 return COMPST_DONE; 205 } else { 206 return COMPST_CHECK_ACK; 207 } 208 } 209 210 static inline enum comp_state check_ack(struct rxe_qp *qp, 211 struct rxe_pkt_info *pkt, 212 struct rxe_send_wqe *wqe) 213 { 214 unsigned int mask = pkt->mask; 215 u8 syn; 216 struct rxe_dev *rxe = to_rdev(qp->ibqp.device); 217 218 /* Check the sequence only */ 219 switch (qp->comp.opcode) { 220 case -1: 221 /* Will catch all *_ONLY cases. */ 222 if (!(mask & RXE_START_MASK)) 223 return COMPST_ERROR; 224 225 break; 226 227 case IB_OPCODE_RC_RDMA_READ_RESPONSE_FIRST: 228 case IB_OPCODE_RC_RDMA_READ_RESPONSE_MIDDLE: 229 if (pkt->opcode != IB_OPCODE_RC_RDMA_READ_RESPONSE_MIDDLE && 230 pkt->opcode != IB_OPCODE_RC_RDMA_READ_RESPONSE_LAST) { 231 /* read retries of partial data may restart from 232 * read response first or response only. 233 */ 234 if ((pkt->psn == wqe->first_psn && 235 pkt->opcode == 236 IB_OPCODE_RC_RDMA_READ_RESPONSE_FIRST) || 237 (wqe->first_psn == wqe->last_psn && 238 pkt->opcode == 239 IB_OPCODE_RC_RDMA_READ_RESPONSE_ONLY)) 240 break; 241 242 return COMPST_ERROR; 243 } 244 break; 245 default: 246 WARN_ON_ONCE(1); 247 } 248 249 /* Check operation validity. */ 250 switch (pkt->opcode) { 251 case IB_OPCODE_RC_RDMA_READ_RESPONSE_FIRST: 252 case IB_OPCODE_RC_RDMA_READ_RESPONSE_LAST: 253 case IB_OPCODE_RC_RDMA_READ_RESPONSE_ONLY: 254 syn = aeth_syn(pkt); 255 256 if ((syn & AETH_TYPE_MASK) != AETH_ACK) 257 return COMPST_ERROR; 258 259 fallthrough; 260 /* (IB_OPCODE_RC_RDMA_READ_RESPONSE_MIDDLE doesn't have an AETH) 261 */ 262 case IB_OPCODE_RC_RDMA_READ_RESPONSE_MIDDLE: 263 if (wqe->wr.opcode != IB_WR_RDMA_READ && 264 wqe->wr.opcode != IB_WR_RDMA_READ_WITH_INV) { 265 wqe->status = IB_WC_FATAL_ERR; 266 return COMPST_ERROR; 267 } 268 reset_retry_counters(qp); 269 return COMPST_READ; 270 271 case IB_OPCODE_RC_ATOMIC_ACKNOWLEDGE: 272 syn = aeth_syn(pkt); 273 274 if ((syn & AETH_TYPE_MASK) != AETH_ACK) 275 return COMPST_ERROR; 276 277 if (wqe->wr.opcode != IB_WR_ATOMIC_CMP_AND_SWP && 278 wqe->wr.opcode != IB_WR_ATOMIC_FETCH_AND_ADD) 279 return COMPST_ERROR; 280 reset_retry_counters(qp); 281 return COMPST_ATOMIC; 282 283 case IB_OPCODE_RC_ACKNOWLEDGE: 284 syn = aeth_syn(pkt); 285 switch (syn & AETH_TYPE_MASK) { 286 case AETH_ACK: 287 reset_retry_counters(qp); 288 return COMPST_WRITE_SEND; 289 290 case AETH_RNR_NAK: 291 rxe_counter_inc(rxe, RXE_CNT_RCV_RNR); 292 return COMPST_RNR_RETRY; 293 294 case AETH_NAK: 295 switch (syn) { 296 case AETH_NAK_PSN_SEQ_ERROR: 297 /* a nak implicitly acks all packets with psns 298 * before 299 */ 300 if (psn_compare(pkt->psn, qp->comp.psn) > 0) { 301 rxe_counter_inc(rxe, 302 RXE_CNT_RCV_SEQ_ERR); 303 qp->comp.psn = pkt->psn; 304 if (qp->req.wait_psn) { 305 qp->req.wait_psn = 0; 306 rxe_run_task(&qp->req.task, 0); 307 } 308 } 309 return COMPST_ERROR_RETRY; 310 311 case AETH_NAK_INVALID_REQ: 312 wqe->status = IB_WC_REM_INV_REQ_ERR; 313 return COMPST_ERROR; 314 315 case AETH_NAK_REM_ACC_ERR: 316 wqe->status = IB_WC_REM_ACCESS_ERR; 317 return COMPST_ERROR; 318 319 case AETH_NAK_REM_OP_ERR: 320 wqe->status = IB_WC_REM_OP_ERR; 321 return COMPST_ERROR; 322 323 default: 324 pr_warn("unexpected nak %x\n", syn); 325 wqe->status = IB_WC_REM_OP_ERR; 326 return COMPST_ERROR; 327 } 328 329 default: 330 return COMPST_ERROR; 331 } 332 break; 333 334 default: 335 pr_warn("unexpected opcode\n"); 336 } 337 338 return COMPST_ERROR; 339 } 340 341 static inline enum comp_state do_read(struct rxe_qp *qp, 342 struct rxe_pkt_info *pkt, 343 struct rxe_send_wqe *wqe) 344 { 345 int ret; 346 347 ret = copy_data(qp->pd, IB_ACCESS_LOCAL_WRITE, 348 &wqe->dma, payload_addr(pkt), 349 payload_size(pkt), RXE_TO_MR_OBJ); 350 if (ret) { 351 wqe->status = IB_WC_LOC_PROT_ERR; 352 return COMPST_ERROR; 353 } 354 355 if (wqe->dma.resid == 0 && (pkt->mask & RXE_END_MASK)) 356 return COMPST_COMP_ACK; 357 358 return COMPST_UPDATE_COMP; 359 } 360 361 static inline enum comp_state do_atomic(struct rxe_qp *qp, 362 struct rxe_pkt_info *pkt, 363 struct rxe_send_wqe *wqe) 364 { 365 int ret; 366 367 u64 atomic_orig = atmack_orig(pkt); 368 369 ret = copy_data(qp->pd, IB_ACCESS_LOCAL_WRITE, 370 &wqe->dma, &atomic_orig, 371 sizeof(u64), RXE_TO_MR_OBJ); 372 if (ret) { 373 wqe->status = IB_WC_LOC_PROT_ERR; 374 return COMPST_ERROR; 375 } 376 377 return COMPST_COMP_ACK; 378 } 379 380 static void make_send_cqe(struct rxe_qp *qp, struct rxe_send_wqe *wqe, 381 struct rxe_cqe *cqe) 382 { 383 struct ib_wc *wc = &cqe->ibwc; 384 struct ib_uverbs_wc *uwc = &cqe->uibwc; 385 386 memset(cqe, 0, sizeof(*cqe)); 387 388 if (!qp->is_user) { 389 wc->wr_id = wqe->wr.wr_id; 390 wc->status = wqe->status; 391 wc->qp = &qp->ibqp; 392 } else { 393 uwc->wr_id = wqe->wr.wr_id; 394 uwc->status = wqe->status; 395 uwc->qp_num = qp->ibqp.qp_num; 396 } 397 398 if (wqe->status == IB_WC_SUCCESS) { 399 if (!qp->is_user) { 400 wc->opcode = wr_to_wc_opcode(wqe->wr.opcode); 401 if (wqe->wr.opcode == IB_WR_RDMA_WRITE_WITH_IMM || 402 wqe->wr.opcode == IB_WR_SEND_WITH_IMM) 403 wc->wc_flags = IB_WC_WITH_IMM; 404 wc->byte_len = wqe->dma.length; 405 } else { 406 uwc->opcode = wr_to_wc_opcode(wqe->wr.opcode); 407 if (wqe->wr.opcode == IB_WR_RDMA_WRITE_WITH_IMM || 408 wqe->wr.opcode == IB_WR_SEND_WITH_IMM) 409 uwc->wc_flags = IB_WC_WITH_IMM; 410 uwc->byte_len = wqe->dma.length; 411 } 412 } 413 } 414 415 /* 416 * IBA Spec. Section 10.7.3.1 SIGNALED COMPLETIONS 417 * ---------8<---------8<------------- 418 * ...Note that if a completion error occurs, a Work Completion 419 * will always be generated, even if the signaling 420 * indicator requests an Unsignaled Completion. 421 * ---------8<---------8<------------- 422 */ 423 static void do_complete(struct rxe_qp *qp, struct rxe_send_wqe *wqe) 424 { 425 struct rxe_dev *rxe = to_rdev(qp->ibqp.device); 426 struct rxe_cqe cqe; 427 bool post; 428 429 /* do we need to post a completion */ 430 post = ((qp->sq_sig_type == IB_SIGNAL_ALL_WR) || 431 (wqe->wr.send_flags & IB_SEND_SIGNALED) || 432 wqe->status != IB_WC_SUCCESS); 433 434 if (post) 435 make_send_cqe(qp, wqe, &cqe); 436 437 queue_advance_consumer(qp->sq.queue, QUEUE_TYPE_FROM_CLIENT); 438 439 if (post) 440 rxe_cq_post(qp->scq, &cqe, 0); 441 442 if (wqe->wr.opcode == IB_WR_SEND || 443 wqe->wr.opcode == IB_WR_SEND_WITH_IMM || 444 wqe->wr.opcode == IB_WR_SEND_WITH_INV) 445 rxe_counter_inc(rxe, RXE_CNT_RDMA_SEND); 446 447 /* 448 * we completed something so let req run again 449 * if it is trying to fence 450 */ 451 if (qp->req.wait_fence) { 452 qp->req.wait_fence = 0; 453 rxe_run_task(&qp->req.task, 0); 454 } 455 } 456 457 static inline enum comp_state complete_ack(struct rxe_qp *qp, 458 struct rxe_pkt_info *pkt, 459 struct rxe_send_wqe *wqe) 460 { 461 if (wqe->has_rd_atomic) { 462 wqe->has_rd_atomic = 0; 463 atomic_inc(&qp->req.rd_atomic); 464 if (qp->req.need_rd_atomic) { 465 qp->comp.timeout_retry = 0; 466 qp->req.need_rd_atomic = 0; 467 rxe_run_task(&qp->req.task, 0); 468 } 469 } 470 471 if (unlikely(qp->req.state == QP_STATE_DRAIN)) { 472 /* state_lock used by requester & completer */ 473 spin_lock_bh(&qp->state_lock); 474 if ((qp->req.state == QP_STATE_DRAIN) && 475 (qp->comp.psn == qp->req.psn)) { 476 qp->req.state = QP_STATE_DRAINED; 477 spin_unlock_bh(&qp->state_lock); 478 479 if (qp->ibqp.event_handler) { 480 struct ib_event ev; 481 482 ev.device = qp->ibqp.device; 483 ev.element.qp = &qp->ibqp; 484 ev.event = IB_EVENT_SQ_DRAINED; 485 qp->ibqp.event_handler(&ev, 486 qp->ibqp.qp_context); 487 } 488 } else { 489 spin_unlock_bh(&qp->state_lock); 490 } 491 } 492 493 do_complete(qp, wqe); 494 495 if (psn_compare(pkt->psn, qp->comp.psn) >= 0) 496 return COMPST_UPDATE_COMP; 497 else 498 return COMPST_DONE; 499 } 500 501 static inline enum comp_state complete_wqe(struct rxe_qp *qp, 502 struct rxe_pkt_info *pkt, 503 struct rxe_send_wqe *wqe) 504 { 505 if (pkt && wqe->state == wqe_state_pending) { 506 if (psn_compare(wqe->last_psn, qp->comp.psn) >= 0) { 507 qp->comp.psn = (wqe->last_psn + 1) & BTH_PSN_MASK; 508 qp->comp.opcode = -1; 509 } 510 511 if (qp->req.wait_psn) { 512 qp->req.wait_psn = 0; 513 rxe_run_task(&qp->req.task, 1); 514 } 515 } 516 517 do_complete(qp, wqe); 518 519 return COMPST_GET_WQE; 520 } 521 522 static void rxe_drain_resp_pkts(struct rxe_qp *qp, bool notify) 523 { 524 struct sk_buff *skb; 525 struct rxe_send_wqe *wqe; 526 struct rxe_queue *q = qp->sq.queue; 527 528 while ((skb = skb_dequeue(&qp->resp_pkts))) { 529 rxe_put(qp); 530 kfree_skb(skb); 531 ib_device_put(qp->ibqp.device); 532 } 533 534 while ((wqe = queue_head(q, q->type))) { 535 if (notify) { 536 wqe->status = IB_WC_WR_FLUSH_ERR; 537 do_complete(qp, wqe); 538 } else { 539 queue_advance_consumer(q, q->type); 540 } 541 } 542 } 543 544 static void free_pkt(struct rxe_pkt_info *pkt) 545 { 546 struct sk_buff *skb = PKT_TO_SKB(pkt); 547 struct rxe_qp *qp = pkt->qp; 548 struct ib_device *dev = qp->ibqp.device; 549 550 kfree_skb(skb); 551 rxe_put(qp); 552 ib_device_put(dev); 553 } 554 555 int rxe_completer(void *arg) 556 { 557 struct rxe_qp *qp = (struct rxe_qp *)arg; 558 struct rxe_dev *rxe = to_rdev(qp->ibqp.device); 559 struct rxe_send_wqe *wqe = NULL; 560 struct sk_buff *skb = NULL; 561 struct rxe_pkt_info *pkt = NULL; 562 enum comp_state state; 563 int ret = 0; 564 565 rxe_get(qp); 566 567 if (!qp->valid || qp->req.state == QP_STATE_ERROR || 568 qp->req.state == QP_STATE_RESET) { 569 rxe_drain_resp_pkts(qp, qp->valid && 570 qp->req.state == QP_STATE_ERROR); 571 ret = -EAGAIN; 572 goto done; 573 } 574 575 if (qp->comp.timeout) { 576 qp->comp.timeout_retry = 1; 577 qp->comp.timeout = 0; 578 } else { 579 qp->comp.timeout_retry = 0; 580 } 581 582 if (qp->req.need_retry) { 583 ret = -EAGAIN; 584 goto done; 585 } 586 587 state = COMPST_GET_ACK; 588 589 while (1) { 590 pr_debug("qp#%d state = %s\n", qp_num(qp), 591 comp_state_name[state]); 592 switch (state) { 593 case COMPST_GET_ACK: 594 skb = skb_dequeue(&qp->resp_pkts); 595 if (skb) { 596 pkt = SKB_TO_PKT(skb); 597 qp->comp.timeout_retry = 0; 598 } 599 state = COMPST_GET_WQE; 600 break; 601 602 case COMPST_GET_WQE: 603 state = get_wqe(qp, pkt, &wqe); 604 break; 605 606 case COMPST_CHECK_PSN: 607 state = check_psn(qp, pkt, wqe); 608 break; 609 610 case COMPST_CHECK_ACK: 611 state = check_ack(qp, pkt, wqe); 612 break; 613 614 case COMPST_READ: 615 state = do_read(qp, pkt, wqe); 616 break; 617 618 case COMPST_ATOMIC: 619 state = do_atomic(qp, pkt, wqe); 620 break; 621 622 case COMPST_WRITE_SEND: 623 if (wqe->state == wqe_state_pending && 624 wqe->last_psn == pkt->psn) 625 state = COMPST_COMP_ACK; 626 else 627 state = COMPST_UPDATE_COMP; 628 break; 629 630 case COMPST_COMP_ACK: 631 state = complete_ack(qp, pkt, wqe); 632 break; 633 634 case COMPST_COMP_WQE: 635 state = complete_wqe(qp, pkt, wqe); 636 break; 637 638 case COMPST_UPDATE_COMP: 639 if (pkt->mask & RXE_END_MASK) 640 qp->comp.opcode = -1; 641 else 642 qp->comp.opcode = pkt->opcode; 643 644 if (psn_compare(pkt->psn, qp->comp.psn) >= 0) 645 qp->comp.psn = (pkt->psn + 1) & BTH_PSN_MASK; 646 647 if (qp->req.wait_psn) { 648 qp->req.wait_psn = 0; 649 rxe_run_task(&qp->req.task, 1); 650 } 651 652 state = COMPST_DONE; 653 break; 654 655 case COMPST_DONE: 656 goto done; 657 658 case COMPST_EXIT: 659 if (qp->comp.timeout_retry && wqe) { 660 state = COMPST_ERROR_RETRY; 661 break; 662 } 663 664 /* re reset the timeout counter if 665 * (1) QP is type RC 666 * (2) the QP is alive 667 * (3) there is a packet sent by the requester that 668 * might be acked (we still might get spurious 669 * timeouts but try to keep them as few as possible) 670 * (4) the timeout parameter is set 671 */ 672 if ((qp_type(qp) == IB_QPT_RC) && 673 (qp->req.state == QP_STATE_READY) && 674 (psn_compare(qp->req.psn, qp->comp.psn) > 0) && 675 qp->qp_timeout_jiffies) 676 mod_timer(&qp->retrans_timer, 677 jiffies + qp->qp_timeout_jiffies); 678 ret = -EAGAIN; 679 goto done; 680 681 case COMPST_ERROR_RETRY: 682 /* we come here if the retry timer fired and we did 683 * not receive a response packet. try to retry the send 684 * queue if that makes sense and the limits have not 685 * been exceeded. remember that some timeouts are 686 * spurious since we do not reset the timer but kick 687 * it down the road or let it expire 688 */ 689 690 /* there is nothing to retry in this case */ 691 if (!wqe || (wqe->state == wqe_state_posted)) { 692 ret = -EAGAIN; 693 goto done; 694 } 695 696 /* if we've started a retry, don't start another 697 * retry sequence, unless this is a timeout. 698 */ 699 if (qp->comp.started_retry && 700 !qp->comp.timeout_retry) 701 goto done; 702 703 if (qp->comp.retry_cnt > 0) { 704 if (qp->comp.retry_cnt != 7) 705 qp->comp.retry_cnt--; 706 707 /* no point in retrying if we have already 708 * seen the last ack that the requester could 709 * have caused 710 */ 711 if (psn_compare(qp->req.psn, 712 qp->comp.psn) > 0) { 713 /* tell the requester to retry the 714 * send queue next time around 715 */ 716 rxe_counter_inc(rxe, 717 RXE_CNT_COMP_RETRY); 718 qp->req.need_retry = 1; 719 qp->comp.started_retry = 1; 720 rxe_run_task(&qp->req.task, 0); 721 } 722 goto done; 723 724 } else { 725 rxe_counter_inc(rxe, RXE_CNT_RETRY_EXCEEDED); 726 wqe->status = IB_WC_RETRY_EXC_ERR; 727 state = COMPST_ERROR; 728 } 729 break; 730 731 case COMPST_RNR_RETRY: 732 if (qp->comp.rnr_retry > 0) { 733 if (qp->comp.rnr_retry != 7) 734 qp->comp.rnr_retry--; 735 736 qp->req.need_retry = 1; 737 pr_debug("qp#%d set rnr nak timer\n", 738 qp_num(qp)); 739 mod_timer(&qp->rnr_nak_timer, 740 jiffies + rnrnak_jiffies(aeth_syn(pkt) 741 & ~AETH_TYPE_MASK)); 742 ret = -EAGAIN; 743 goto done; 744 } else { 745 rxe_counter_inc(rxe, 746 RXE_CNT_RNR_RETRY_EXCEEDED); 747 wqe->status = IB_WC_RNR_RETRY_EXC_ERR; 748 state = COMPST_ERROR; 749 } 750 break; 751 752 case COMPST_ERROR: 753 WARN_ON_ONCE(wqe->status == IB_WC_SUCCESS); 754 do_complete(qp, wqe); 755 rxe_qp_error(qp); 756 ret = -EAGAIN; 757 goto done; 758 } 759 } 760 761 done: 762 if (pkt) 763 free_pkt(pkt); 764 rxe_put(qp); 765 766 return ret; 767 } 768