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 14enum 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 32static 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 50static 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 85static inline unsigned long rnrnak_jiffies(u8 timeout) 86{ 87 return max_t(unsigned long, 88 usecs_to_jiffies(rnrnak_usec[timeout]), 1); 89} 90 91static 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 case IB_WR_ATOMIC_WRITE: return IB_WC_ATOMIC_WRITE; 108 case IB_WR_FLUSH: return IB_WC_FLUSH; 109 110 default: 111 return 0xff; 112 } 113} 114 115void retransmit_timer(struct timer_list *t) 116{ 117 struct rxe_qp *qp = from_timer(qp, t, retrans_timer); 118 unsigned long flags; 119 120 rxe_dbg_qp(qp, "retransmit timer fired\n"); 121 122 spin_lock_irqsave(&qp->state_lock, flags); 123 if (qp->valid) { 124 qp->comp.timeout = 1; 125 rxe_sched_task(&qp->comp.task); 126 } 127 spin_unlock_irqrestore(&qp->state_lock, flags); 128} 129 130void rxe_comp_queue_pkt(struct rxe_qp *qp, struct sk_buff *skb) 131{ 132 int must_sched; 133 134 skb_queue_tail(&qp->resp_pkts, skb); 135 136 must_sched = skb_queue_len(&qp->resp_pkts) > 1; 137 if (must_sched != 0) 138 rxe_counter_inc(SKB_TO_PKT(skb)->rxe, RXE_CNT_COMPLETER_SCHED); 139 140 if (must_sched) 141 rxe_sched_task(&qp->comp.task); 142 else 143 rxe_run_task(&qp->comp.task); 144} 145 146static inline enum comp_state get_wqe(struct rxe_qp *qp, 147 struct rxe_pkt_info *pkt, 148 struct rxe_send_wqe **wqe_p) 149{ 150 struct rxe_send_wqe *wqe; 151 152 /* we come here whether or not we found a response packet to see if 153 * there are any posted WQEs 154 */ 155 wqe = queue_head(qp->sq.queue, QUEUE_TYPE_FROM_CLIENT); 156 *wqe_p = wqe; 157 158 /* no WQE or requester has not started it yet */ 159 if (!wqe || wqe->state == wqe_state_posted) 160 return pkt ? COMPST_DONE : COMPST_EXIT; 161 162 /* WQE does not require an ack */ 163 if (wqe->state == wqe_state_done) 164 return COMPST_COMP_WQE; 165 166 /* WQE caused an error */ 167 if (wqe->state == wqe_state_error) 168 return COMPST_ERROR; 169 170 /* we have a WQE, if we also have an ack check its PSN */ 171 return pkt ? COMPST_CHECK_PSN : COMPST_EXIT; 172} 173 174static inline void reset_retry_counters(struct rxe_qp *qp) 175{ 176 qp->comp.retry_cnt = qp->attr.retry_cnt; 177 qp->comp.rnr_retry = qp->attr.rnr_retry; 178 qp->comp.started_retry = 0; 179} 180 181static inline enum comp_state check_psn(struct rxe_qp *qp, 182 struct rxe_pkt_info *pkt, 183 struct rxe_send_wqe *wqe) 184{ 185 s32 diff; 186 187 /* check to see if response is past the oldest WQE. if it is, complete 188 * send/write or error read/atomic 189 */ 190 diff = psn_compare(pkt->psn, wqe->last_psn); 191 if (diff > 0) { 192 if (wqe->state == wqe_state_pending) { 193 if (wqe->mask & WR_ATOMIC_OR_READ_MASK) 194 return COMPST_ERROR_RETRY; 195 196 reset_retry_counters(qp); 197 return COMPST_COMP_WQE; 198 } else { 199 return COMPST_DONE; 200 } 201 } 202 203 /* compare response packet to expected response */ 204 diff = psn_compare(pkt->psn, qp->comp.psn); 205 if (diff < 0) { 206 /* response is most likely a retried packet if it matches an 207 * uncompleted WQE go complete it else ignore it 208 */ 209 if (pkt->psn == wqe->last_psn) 210 return COMPST_COMP_ACK; 211 else if (pkt->opcode == IB_OPCODE_RC_ACKNOWLEDGE && 212 (qp->comp.opcode == IB_OPCODE_RC_RDMA_READ_RESPONSE_FIRST || 213 qp->comp.opcode == IB_OPCODE_RC_RDMA_READ_RESPONSE_MIDDLE)) 214 return COMPST_CHECK_ACK; 215 else 216 return COMPST_DONE; 217 } else if ((diff > 0) && (wqe->mask & WR_ATOMIC_OR_READ_MASK)) { 218 return COMPST_DONE; 219 } else { 220 return COMPST_CHECK_ACK; 221 } 222} 223 224static inline enum comp_state check_ack(struct rxe_qp *qp, 225 struct rxe_pkt_info *pkt, 226 struct rxe_send_wqe *wqe) 227{ 228 unsigned int mask = pkt->mask; 229 u8 syn; 230 struct rxe_dev *rxe = to_rdev(qp->ibqp.device); 231 232 /* Check the sequence only */ 233 switch (qp->comp.opcode) { 234 case -1: 235 /* Will catch all *_ONLY cases. */ 236 if (!(mask & RXE_START_MASK)) 237 return COMPST_ERROR; 238 239 break; 240 241 case IB_OPCODE_RC_RDMA_READ_RESPONSE_FIRST: 242 case IB_OPCODE_RC_RDMA_READ_RESPONSE_MIDDLE: 243 /* Check NAK code to handle a remote error */ 244 if (pkt->opcode == IB_OPCODE_RC_ACKNOWLEDGE) 245 break; 246 247 if (pkt->opcode != IB_OPCODE_RC_RDMA_READ_RESPONSE_MIDDLE && 248 pkt->opcode != IB_OPCODE_RC_RDMA_READ_RESPONSE_LAST) { 249 /* read retries of partial data may restart from 250 * read response first or response only. 251 */ 252 if ((pkt->psn == wqe->first_psn && 253 pkt->opcode == 254 IB_OPCODE_RC_RDMA_READ_RESPONSE_FIRST) || 255 (wqe->first_psn == wqe->last_psn && 256 pkt->opcode == 257 IB_OPCODE_RC_RDMA_READ_RESPONSE_ONLY)) 258 break; 259 260 return COMPST_ERROR; 261 } 262 break; 263 default: 264 WARN_ON_ONCE(1); 265 } 266 267 /* Check operation validity. */ 268 switch (pkt->opcode) { 269 case IB_OPCODE_RC_RDMA_READ_RESPONSE_FIRST: 270 case IB_OPCODE_RC_RDMA_READ_RESPONSE_LAST: 271 case IB_OPCODE_RC_RDMA_READ_RESPONSE_ONLY: 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_WRITE) 278 return COMPST_WRITE_SEND; 279 280 fallthrough; 281 /* (IB_OPCODE_RC_RDMA_READ_RESPONSE_MIDDLE doesn't have an AETH) 282 */ 283 case IB_OPCODE_RC_RDMA_READ_RESPONSE_MIDDLE: 284 if (wqe->wr.opcode != IB_WR_RDMA_READ && 285 wqe->wr.opcode != IB_WR_RDMA_READ_WITH_INV && 286 wqe->wr.opcode != IB_WR_FLUSH) { 287 wqe->status = IB_WC_FATAL_ERR; 288 return COMPST_ERROR; 289 } 290 reset_retry_counters(qp); 291 return COMPST_READ; 292 293 case IB_OPCODE_RC_ATOMIC_ACKNOWLEDGE: 294 syn = aeth_syn(pkt); 295 296 if ((syn & AETH_TYPE_MASK) != AETH_ACK) 297 return COMPST_ERROR; 298 299 if (wqe->wr.opcode != IB_WR_ATOMIC_CMP_AND_SWP && 300 wqe->wr.opcode != IB_WR_ATOMIC_FETCH_AND_ADD) 301 return COMPST_ERROR; 302 reset_retry_counters(qp); 303 return COMPST_ATOMIC; 304 305 case IB_OPCODE_RC_ACKNOWLEDGE: 306 syn = aeth_syn(pkt); 307 switch (syn & AETH_TYPE_MASK) { 308 case AETH_ACK: 309 reset_retry_counters(qp); 310 return COMPST_WRITE_SEND; 311 312 case AETH_RNR_NAK: 313 rxe_counter_inc(rxe, RXE_CNT_RCV_RNR); 314 return COMPST_RNR_RETRY; 315 316 case AETH_NAK: 317 switch (syn) { 318 case AETH_NAK_PSN_SEQ_ERROR: 319 /* a nak implicitly acks all packets with psns 320 * before 321 */ 322 if (psn_compare(pkt->psn, qp->comp.psn) > 0) { 323 rxe_counter_inc(rxe, 324 RXE_CNT_RCV_SEQ_ERR); 325 qp->comp.psn = pkt->psn; 326 if (qp->req.wait_psn) { 327 qp->req.wait_psn = 0; 328 rxe_sched_task(&qp->req.task); 329 } 330 } 331 return COMPST_ERROR_RETRY; 332 333 case AETH_NAK_INVALID_REQ: 334 wqe->status = IB_WC_REM_INV_REQ_ERR; 335 return COMPST_ERROR; 336 337 case AETH_NAK_REM_ACC_ERR: 338 wqe->status = IB_WC_REM_ACCESS_ERR; 339 return COMPST_ERROR; 340 341 case AETH_NAK_REM_OP_ERR: 342 wqe->status = IB_WC_REM_OP_ERR; 343 return COMPST_ERROR; 344 345 default: 346 rxe_dbg_qp(qp, "unexpected nak %x\n", syn); 347 wqe->status = IB_WC_REM_OP_ERR; 348 return COMPST_ERROR; 349 } 350 351 default: 352 return COMPST_ERROR; 353 } 354 break; 355 356 default: 357 rxe_dbg_qp(qp, "unexpected opcode\n"); 358 } 359 360 return COMPST_ERROR; 361} 362 363static inline enum comp_state do_read(struct rxe_qp *qp, 364 struct rxe_pkt_info *pkt, 365 struct rxe_send_wqe *wqe) 366{ 367 int ret; 368 369 ret = copy_data(qp->pd, IB_ACCESS_LOCAL_WRITE, 370 &wqe->dma, payload_addr(pkt), 371 payload_size(pkt), RXE_TO_MR_OBJ); 372 if (ret) { 373 wqe->status = IB_WC_LOC_PROT_ERR; 374 return COMPST_ERROR; 375 } 376 377 if (wqe->dma.resid == 0 && (pkt->mask & RXE_END_MASK)) 378 return COMPST_COMP_ACK; 379 380 return COMPST_UPDATE_COMP; 381} 382 383static inline enum comp_state do_atomic(struct rxe_qp *qp, 384 struct rxe_pkt_info *pkt, 385 struct rxe_send_wqe *wqe) 386{ 387 int ret; 388 389 u64 atomic_orig = atmack_orig(pkt); 390 391 ret = copy_data(qp->pd, IB_ACCESS_LOCAL_WRITE, 392 &wqe->dma, &atomic_orig, 393 sizeof(u64), RXE_TO_MR_OBJ); 394 if (ret) { 395 wqe->status = IB_WC_LOC_PROT_ERR; 396 return COMPST_ERROR; 397 } 398 399 return COMPST_COMP_ACK; 400} 401 402static void make_send_cqe(struct rxe_qp *qp, struct rxe_send_wqe *wqe, 403 struct rxe_cqe *cqe) 404{ 405 struct ib_wc *wc = &cqe->ibwc; 406 struct ib_uverbs_wc *uwc = &cqe->uibwc; 407 408 memset(cqe, 0, sizeof(*cqe)); 409 410 if (!qp->is_user) { 411 wc->wr_id = wqe->wr.wr_id; 412 wc->status = wqe->status; 413 wc->qp = &qp->ibqp; 414 } else { 415 uwc->wr_id = wqe->wr.wr_id; 416 uwc->status = wqe->status; 417 uwc->qp_num = qp->ibqp.qp_num; 418 } 419 420 if (wqe->status == IB_WC_SUCCESS) { 421 if (!qp->is_user) { 422 wc->opcode = wr_to_wc_opcode(wqe->wr.opcode); 423 if (wqe->wr.opcode == IB_WR_RDMA_WRITE_WITH_IMM || 424 wqe->wr.opcode == IB_WR_SEND_WITH_IMM) 425 wc->wc_flags = IB_WC_WITH_IMM; 426 wc->byte_len = wqe->dma.length; 427 } else { 428 uwc->opcode = wr_to_wc_opcode(wqe->wr.opcode); 429 if (wqe->wr.opcode == IB_WR_RDMA_WRITE_WITH_IMM || 430 wqe->wr.opcode == IB_WR_SEND_WITH_IMM) 431 uwc->wc_flags = IB_WC_WITH_IMM; 432 uwc->byte_len = wqe->dma.length; 433 } 434 } else { 435 if (wqe->status != IB_WC_WR_FLUSH_ERR) 436 rxe_err_qp(qp, "non-flush error status = %d\n", 437 wqe->status); 438 } 439} 440 441/* 442 * IBA Spec. Section 10.7.3.1 SIGNALED COMPLETIONS 443 * ---------8<---------8<------------- 444 * ...Note that if a completion error occurs, a Work Completion 445 * will always be generated, even if the signaling 446 * indicator requests an Unsignaled Completion. 447 * ---------8<---------8<------------- 448 */ 449static void do_complete(struct rxe_qp *qp, struct rxe_send_wqe *wqe) 450{ 451 struct rxe_dev *rxe = to_rdev(qp->ibqp.device); 452 struct rxe_cqe cqe; 453 bool post; 454 455 /* do we need to post a completion */ 456 post = ((qp->sq_sig_type == IB_SIGNAL_ALL_WR) || 457 (wqe->wr.send_flags & IB_SEND_SIGNALED) || 458 wqe->status != IB_WC_SUCCESS); 459 460 if (post) 461 make_send_cqe(qp, wqe, &cqe); 462 463 queue_advance_consumer(qp->sq.queue, QUEUE_TYPE_FROM_CLIENT); 464 465 if (post) 466 rxe_cq_post(qp->scq, &cqe, 0); 467 468 if (wqe->wr.opcode == IB_WR_SEND || 469 wqe->wr.opcode == IB_WR_SEND_WITH_IMM || 470 wqe->wr.opcode == IB_WR_SEND_WITH_INV) 471 rxe_counter_inc(rxe, RXE_CNT_RDMA_SEND); 472 473 /* 474 * we completed something so let req run again 475 * if it is trying to fence 476 */ 477 if (qp->req.wait_fence) { 478 qp->req.wait_fence = 0; 479 rxe_sched_task(&qp->req.task); 480 } 481} 482 483static void comp_check_sq_drain_done(struct rxe_qp *qp) 484{ 485 unsigned long flags; 486 487 spin_lock_irqsave(&qp->state_lock, flags); 488 if (unlikely(qp_state(qp) == IB_QPS_SQD)) { 489 if (qp->attr.sq_draining && qp->comp.psn == qp->req.psn) { 490 qp->attr.sq_draining = 0; 491 spin_unlock_irqrestore(&qp->state_lock, flags); 492 493 if (qp->ibqp.event_handler) { 494 struct ib_event ev; 495 496 ev.device = qp->ibqp.device; 497 ev.element.qp = &qp->ibqp; 498 ev.event = IB_EVENT_SQ_DRAINED; 499 qp->ibqp.event_handler(&ev, 500 qp->ibqp.qp_context); 501 } 502 return; 503 } 504 } 505 spin_unlock_irqrestore(&qp->state_lock, flags); 506} 507 508static inline enum comp_state complete_ack(struct rxe_qp *qp, 509 struct rxe_pkt_info *pkt, 510 struct rxe_send_wqe *wqe) 511{ 512 if (wqe->has_rd_atomic) { 513 wqe->has_rd_atomic = 0; 514 atomic_inc(&qp->req.rd_atomic); 515 if (qp->req.need_rd_atomic) { 516 qp->comp.timeout_retry = 0; 517 qp->req.need_rd_atomic = 0; 518 rxe_sched_task(&qp->req.task); 519 } 520 } 521 522 comp_check_sq_drain_done(qp); 523 524 do_complete(qp, wqe); 525 526 if (psn_compare(pkt->psn, qp->comp.psn) >= 0) 527 return COMPST_UPDATE_COMP; 528 else 529 return COMPST_DONE; 530} 531 532static inline enum comp_state complete_wqe(struct rxe_qp *qp, 533 struct rxe_pkt_info *pkt, 534 struct rxe_send_wqe *wqe) 535{ 536 if (pkt && wqe->state == wqe_state_pending) { 537 if (psn_compare(wqe->last_psn, qp->comp.psn) >= 0) { 538 qp->comp.psn = (wqe->last_psn + 1) & BTH_PSN_MASK; 539 qp->comp.opcode = -1; 540 } 541 542 if (qp->req.wait_psn) { 543 qp->req.wait_psn = 0; 544 rxe_sched_task(&qp->req.task); 545 } 546 } 547 548 do_complete(qp, wqe); 549 550 return COMPST_GET_WQE; 551} 552 553/* drain incoming response packet queue */ 554static void drain_resp_pkts(struct rxe_qp *qp) 555{ 556 struct sk_buff *skb; 557 558 while ((skb = skb_dequeue(&qp->resp_pkts))) { 559 rxe_put(qp); 560 kfree_skb(skb); 561 ib_device_put(qp->ibqp.device); 562 } 563} 564 565/* complete send wqe with flush error */ 566static int flush_send_wqe(struct rxe_qp *qp, struct rxe_send_wqe *wqe) 567{ 568 struct rxe_cqe cqe = {}; 569 struct ib_wc *wc = &cqe.ibwc; 570 struct ib_uverbs_wc *uwc = &cqe.uibwc; 571 int err; 572 573 if (qp->is_user) { 574 uwc->wr_id = wqe->wr.wr_id; 575 uwc->status = IB_WC_WR_FLUSH_ERR; 576 uwc->qp_num = qp->ibqp.qp_num; 577 } else { 578 wc->wr_id = wqe->wr.wr_id; 579 wc->status = IB_WC_WR_FLUSH_ERR; 580 wc->qp = &qp->ibqp; 581 } 582 583 err = rxe_cq_post(qp->scq, &cqe, 0); 584 if (err) 585 rxe_dbg_cq(qp->scq, "post cq failed, err = %d\n", err); 586 587 return err; 588} 589 590/* drain and optionally complete the send queue 591 * if unable to complete a wqe, i.e. cq is full, stop 592 * completing and flush the remaining wqes 593 */ 594static void flush_send_queue(struct rxe_qp *qp, bool notify) 595{ 596 struct rxe_send_wqe *wqe; 597 struct rxe_queue *q = qp->sq.queue; 598 int err; 599 600 /* send queue never got created. nothing to do. */ 601 if (!qp->sq.queue) 602 return; 603 604 while ((wqe = queue_head(q, q->type))) { 605 if (notify) { 606 err = flush_send_wqe(qp, wqe); 607 if (err) 608 notify = 0; 609 } 610 queue_advance_consumer(q, q->type); 611 } 612} 613 614static void free_pkt(struct rxe_pkt_info *pkt) 615{ 616 struct sk_buff *skb = PKT_TO_SKB(pkt); 617 struct rxe_qp *qp = pkt->qp; 618 struct ib_device *dev = qp->ibqp.device; 619 620 kfree_skb(skb); 621 rxe_put(qp); 622 ib_device_put(dev); 623} 624 625/* reset the retry timer if 626 * - QP is type RC 627 * - there is a packet sent by the requester that 628 * might be acked (we still might get spurious 629 * timeouts but try to keep them as few as possible) 630 * - the timeout parameter is set 631 * - the QP is alive 632 */ 633static void reset_retry_timer(struct rxe_qp *qp) 634{ 635 unsigned long flags; 636 637 if (qp_type(qp) == IB_QPT_RC && qp->qp_timeout_jiffies) { 638 spin_lock_irqsave(&qp->state_lock, flags); 639 if (qp_state(qp) >= IB_QPS_RTS && 640 psn_compare(qp->req.psn, qp->comp.psn) > 0) 641 mod_timer(&qp->retrans_timer, 642 jiffies + qp->qp_timeout_jiffies); 643 spin_unlock_irqrestore(&qp->state_lock, flags); 644 } 645} 646 647int rxe_completer(struct rxe_qp *qp) 648{ 649 struct rxe_dev *rxe = to_rdev(qp->ibqp.device); 650 struct rxe_send_wqe *wqe = NULL; 651 struct sk_buff *skb = NULL; 652 struct rxe_pkt_info *pkt = NULL; 653 enum comp_state state; 654 int ret; 655 unsigned long flags; 656 657 spin_lock_irqsave(&qp->state_lock, flags); 658 if (!qp->valid || qp_state(qp) == IB_QPS_ERR || 659 qp_state(qp) == IB_QPS_RESET) { 660 bool notify = qp->valid && (qp_state(qp) == IB_QPS_ERR); 661 662 drain_resp_pkts(qp); 663 flush_send_queue(qp, notify); 664 spin_unlock_irqrestore(&qp->state_lock, flags); 665 goto exit; 666 } 667 spin_unlock_irqrestore(&qp->state_lock, flags); 668 669 if (qp->comp.timeout) { 670 qp->comp.timeout_retry = 1; 671 qp->comp.timeout = 0; 672 } else { 673 qp->comp.timeout_retry = 0; 674 } 675 676 if (qp->req.need_retry) 677 goto exit; 678 679 state = COMPST_GET_ACK; 680 681 while (1) { 682 rxe_dbg_qp(qp, "state = %s\n", comp_state_name[state]); 683 switch (state) { 684 case COMPST_GET_ACK: 685 skb = skb_dequeue(&qp->resp_pkts); 686 if (skb) { 687 pkt = SKB_TO_PKT(skb); 688 qp->comp.timeout_retry = 0; 689 } 690 state = COMPST_GET_WQE; 691 break; 692 693 case COMPST_GET_WQE: 694 state = get_wqe(qp, pkt, &wqe); 695 break; 696 697 case COMPST_CHECK_PSN: 698 state = check_psn(qp, pkt, wqe); 699 break; 700 701 case COMPST_CHECK_ACK: 702 state = check_ack(qp, pkt, wqe); 703 break; 704 705 case COMPST_READ: 706 state = do_read(qp, pkt, wqe); 707 break; 708 709 case COMPST_ATOMIC: 710 state = do_atomic(qp, pkt, wqe); 711 break; 712 713 case COMPST_WRITE_SEND: 714 if (wqe->state == wqe_state_pending && 715 wqe->last_psn == pkt->psn) 716 state = COMPST_COMP_ACK; 717 else 718 state = COMPST_UPDATE_COMP; 719 break; 720 721 case COMPST_COMP_ACK: 722 state = complete_ack(qp, pkt, wqe); 723 break; 724 725 case COMPST_COMP_WQE: 726 state = complete_wqe(qp, pkt, wqe); 727 break; 728 729 case COMPST_UPDATE_COMP: 730 if (pkt->mask & RXE_END_MASK) 731 qp->comp.opcode = -1; 732 else 733 qp->comp.opcode = pkt->opcode; 734 735 if (psn_compare(pkt->psn, qp->comp.psn) >= 0) 736 qp->comp.psn = (pkt->psn + 1) & BTH_PSN_MASK; 737 738 if (qp->req.wait_psn) { 739 qp->req.wait_psn = 0; 740 rxe_sched_task(&qp->req.task); 741 } 742 743 state = COMPST_DONE; 744 break; 745 746 case COMPST_DONE: 747 goto done; 748 749 case COMPST_EXIT: 750 if (qp->comp.timeout_retry && wqe) { 751 state = COMPST_ERROR_RETRY; 752 break; 753 } 754 755 reset_retry_timer(qp); 756 goto exit; 757 758 case COMPST_ERROR_RETRY: 759 /* we come here if the retry timer fired and we did 760 * not receive a response packet. try to retry the send 761 * queue if that makes sense and the limits have not 762 * been exceeded. remember that some timeouts are 763 * spurious since we do not reset the timer but kick 764 * it down the road or let it expire 765 */ 766 767 /* there is nothing to retry in this case */ 768 if (!wqe || (wqe->state == wqe_state_posted)) 769 goto exit; 770 771 /* if we've started a retry, don't start another 772 * retry sequence, unless this is a timeout. 773 */ 774 if (qp->comp.started_retry && 775 !qp->comp.timeout_retry) 776 goto done; 777 778 if (qp->comp.retry_cnt > 0) { 779 if (qp->comp.retry_cnt != 7) 780 qp->comp.retry_cnt--; 781 782 /* no point in retrying if we have already 783 * seen the last ack that the requester could 784 * have caused 785 */ 786 if (psn_compare(qp->req.psn, 787 qp->comp.psn) > 0) { 788 /* tell the requester to retry the 789 * send queue next time around 790 */ 791 rxe_counter_inc(rxe, 792 RXE_CNT_COMP_RETRY); 793 qp->req.need_retry = 1; 794 qp->comp.started_retry = 1; 795 rxe_sched_task(&qp->req.task); 796 } 797 goto done; 798 799 } else { 800 rxe_counter_inc(rxe, RXE_CNT_RETRY_EXCEEDED); 801 wqe->status = IB_WC_RETRY_EXC_ERR; 802 state = COMPST_ERROR; 803 } 804 break; 805 806 case COMPST_RNR_RETRY: 807 /* we come here if we received an RNR NAK */ 808 if (qp->comp.rnr_retry > 0) { 809 if (qp->comp.rnr_retry != 7) 810 qp->comp.rnr_retry--; 811 812 /* don't start a retry flow until the 813 * rnr timer has fired 814 */ 815 qp->req.wait_for_rnr_timer = 1; 816 rxe_dbg_qp(qp, "set rnr nak timer\n"); 817 // TODO who protects from destroy_qp?? 818 mod_timer(&qp->rnr_nak_timer, 819 jiffies + rnrnak_jiffies(aeth_syn(pkt) 820 & ~AETH_TYPE_MASK)); 821 goto exit; 822 } else { 823 rxe_counter_inc(rxe, 824 RXE_CNT_RNR_RETRY_EXCEEDED); 825 wqe->status = IB_WC_RNR_RETRY_EXC_ERR; 826 state = COMPST_ERROR; 827 } 828 break; 829 830 case COMPST_ERROR: 831 WARN_ON_ONCE(wqe->status == IB_WC_SUCCESS); 832 do_complete(qp, wqe); 833 rxe_qp_error(qp); 834 goto exit; 835 } 836 } 837 838 /* A non-zero return value will cause rxe_do_task to 839 * exit its loop and end the work item. A zero return 840 * will continue looping and return to rxe_completer 841 */ 842done: 843 ret = 0; 844 goto out; 845exit: 846 ret = -EAGAIN; 847out: 848 if (pkt) 849 free_pkt(pkt); 850 return ret; 851} 852