1 /* 2 * Copyright (c) 2016 Mellanox Technologies Ltd. All rights reserved. 3 * Copyright (c) 2015 System Fabric Works, Inc. All rights reserved. 4 * 5 * This software is available to you under a choice of one of two 6 * licenses. You may choose to be licensed under the terms of the GNU 7 * General Public License (GPL) Version 2, available from the file 8 * COPYING in the main directory of this source tree, or the 9 * OpenIB.org BSD license below: 10 * 11 * Redistribution and use in source and binary forms, with or 12 * without modification, are permitted provided that the following 13 * conditions are met: 14 * 15 * - Redistributions of source code must retain the above 16 * copyright notice, this list of conditions and the following 17 * disclaimer. 18 * 19 * - Redistributions in binary form must reproduce the above 20 * copyright notice, this list of conditions and the following 21 * disclaimer in the documentation and/or other materials 22 * provided with the distribution. 23 * 24 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 25 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 26 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 27 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 28 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 29 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 30 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 31 * SOFTWARE. 32 */ 33 34 #include <linux/skbuff.h> 35 36 #include "rxe.h" 37 #include "rxe_loc.h" 38 #include "rxe_queue.h" 39 #include "rxe_task.h" 40 41 enum comp_state { 42 COMPST_GET_ACK, 43 COMPST_GET_WQE, 44 COMPST_COMP_WQE, 45 COMPST_COMP_ACK, 46 COMPST_CHECK_PSN, 47 COMPST_CHECK_ACK, 48 COMPST_READ, 49 COMPST_ATOMIC, 50 COMPST_WRITE_SEND, 51 COMPST_UPDATE_COMP, 52 COMPST_ERROR_RETRY, 53 COMPST_RNR_RETRY, 54 COMPST_ERROR, 55 COMPST_EXIT, /* We have an issue, and we want to rerun the completer */ 56 COMPST_DONE, /* The completer finished successflly */ 57 }; 58 59 static char *comp_state_name[] = { 60 [COMPST_GET_ACK] = "GET ACK", 61 [COMPST_GET_WQE] = "GET WQE", 62 [COMPST_COMP_WQE] = "COMP WQE", 63 [COMPST_COMP_ACK] = "COMP ACK", 64 [COMPST_CHECK_PSN] = "CHECK PSN", 65 [COMPST_CHECK_ACK] = "CHECK ACK", 66 [COMPST_READ] = "READ", 67 [COMPST_ATOMIC] = "ATOMIC", 68 [COMPST_WRITE_SEND] = "WRITE/SEND", 69 [COMPST_UPDATE_COMP] = "UPDATE COMP", 70 [COMPST_ERROR_RETRY] = "ERROR RETRY", 71 [COMPST_RNR_RETRY] = "RNR RETRY", 72 [COMPST_ERROR] = "ERROR", 73 [COMPST_EXIT] = "EXIT", 74 [COMPST_DONE] = "DONE", 75 }; 76 77 static unsigned long rnrnak_usec[32] = { 78 [IB_RNR_TIMER_655_36] = 655360, 79 [IB_RNR_TIMER_000_01] = 10, 80 [IB_RNR_TIMER_000_02] = 20, 81 [IB_RNR_TIMER_000_03] = 30, 82 [IB_RNR_TIMER_000_04] = 40, 83 [IB_RNR_TIMER_000_06] = 60, 84 [IB_RNR_TIMER_000_08] = 80, 85 [IB_RNR_TIMER_000_12] = 120, 86 [IB_RNR_TIMER_000_16] = 160, 87 [IB_RNR_TIMER_000_24] = 240, 88 [IB_RNR_TIMER_000_32] = 320, 89 [IB_RNR_TIMER_000_48] = 480, 90 [IB_RNR_TIMER_000_64] = 640, 91 [IB_RNR_TIMER_000_96] = 960, 92 [IB_RNR_TIMER_001_28] = 1280, 93 [IB_RNR_TIMER_001_92] = 1920, 94 [IB_RNR_TIMER_002_56] = 2560, 95 [IB_RNR_TIMER_003_84] = 3840, 96 [IB_RNR_TIMER_005_12] = 5120, 97 [IB_RNR_TIMER_007_68] = 7680, 98 [IB_RNR_TIMER_010_24] = 10240, 99 [IB_RNR_TIMER_015_36] = 15360, 100 [IB_RNR_TIMER_020_48] = 20480, 101 [IB_RNR_TIMER_030_72] = 30720, 102 [IB_RNR_TIMER_040_96] = 40960, 103 [IB_RNR_TIMER_061_44] = 61410, 104 [IB_RNR_TIMER_081_92] = 81920, 105 [IB_RNR_TIMER_122_88] = 122880, 106 [IB_RNR_TIMER_163_84] = 163840, 107 [IB_RNR_TIMER_245_76] = 245760, 108 [IB_RNR_TIMER_327_68] = 327680, 109 [IB_RNR_TIMER_491_52] = 491520, 110 }; 111 112 static inline unsigned long rnrnak_jiffies(u8 timeout) 113 { 114 return max_t(unsigned long, 115 usecs_to_jiffies(rnrnak_usec[timeout]), 1); 116 } 117 118 static enum ib_wc_opcode wr_to_wc_opcode(enum ib_wr_opcode opcode) 119 { 120 switch (opcode) { 121 case IB_WR_RDMA_WRITE: return IB_WC_RDMA_WRITE; 122 case IB_WR_RDMA_WRITE_WITH_IMM: return IB_WC_RDMA_WRITE; 123 case IB_WR_SEND: return IB_WC_SEND; 124 case IB_WR_SEND_WITH_IMM: return IB_WC_SEND; 125 case IB_WR_RDMA_READ: return IB_WC_RDMA_READ; 126 case IB_WR_ATOMIC_CMP_AND_SWP: return IB_WC_COMP_SWAP; 127 case IB_WR_ATOMIC_FETCH_AND_ADD: return IB_WC_FETCH_ADD; 128 case IB_WR_LSO: return IB_WC_LSO; 129 case IB_WR_SEND_WITH_INV: return IB_WC_SEND; 130 case IB_WR_RDMA_READ_WITH_INV: return IB_WC_RDMA_READ; 131 case IB_WR_LOCAL_INV: return IB_WC_LOCAL_INV; 132 case IB_WR_REG_MR: return IB_WC_REG_MR; 133 134 default: 135 return 0xff; 136 } 137 } 138 139 void retransmit_timer(struct timer_list *t) 140 { 141 struct rxe_qp *qp = from_timer(qp, t, retrans_timer); 142 143 if (qp->valid) { 144 qp->comp.timeout = 1; 145 rxe_run_task(&qp->comp.task, 1); 146 } 147 } 148 149 void rxe_comp_queue_pkt(struct rxe_qp *qp, struct sk_buff *skb) 150 { 151 int must_sched; 152 153 skb_queue_tail(&qp->resp_pkts, skb); 154 155 must_sched = skb_queue_len(&qp->resp_pkts) > 1; 156 if (must_sched != 0) 157 rxe_counter_inc(SKB_TO_PKT(skb)->rxe, RXE_CNT_COMPLETER_SCHED); 158 159 rxe_run_task(&qp->comp.task, must_sched); 160 } 161 162 static inline enum comp_state get_wqe(struct rxe_qp *qp, 163 struct rxe_pkt_info *pkt, 164 struct rxe_send_wqe **wqe_p) 165 { 166 struct rxe_send_wqe *wqe; 167 168 /* we come here whether or not we found a response packet to see if 169 * there are any posted WQEs 170 */ 171 wqe = queue_head(qp->sq.queue); 172 *wqe_p = wqe; 173 174 /* no WQE or requester has not started it yet */ 175 if (!wqe || wqe->state == wqe_state_posted) 176 return pkt ? COMPST_DONE : COMPST_EXIT; 177 178 /* WQE does not require an ack */ 179 if (wqe->state == wqe_state_done) 180 return COMPST_COMP_WQE; 181 182 /* WQE caused an error */ 183 if (wqe->state == wqe_state_error) 184 return COMPST_ERROR; 185 186 /* we have a WQE, if we also have an ack check its PSN */ 187 return pkt ? COMPST_CHECK_PSN : COMPST_EXIT; 188 } 189 190 static inline void reset_retry_counters(struct rxe_qp *qp) 191 { 192 qp->comp.retry_cnt = qp->attr.retry_cnt; 193 qp->comp.rnr_retry = qp->attr.rnr_retry; 194 qp->comp.started_retry = 0; 195 } 196 197 static inline enum comp_state check_psn(struct rxe_qp *qp, 198 struct rxe_pkt_info *pkt, 199 struct rxe_send_wqe *wqe) 200 { 201 s32 diff; 202 203 /* check to see if response is past the oldest WQE. if it is, complete 204 * send/write or error read/atomic 205 */ 206 diff = psn_compare(pkt->psn, wqe->last_psn); 207 if (diff > 0) { 208 if (wqe->state == wqe_state_pending) { 209 if (wqe->mask & WR_ATOMIC_OR_READ_MASK) 210 return COMPST_ERROR_RETRY; 211 212 reset_retry_counters(qp); 213 return COMPST_COMP_WQE; 214 } else { 215 return COMPST_DONE; 216 } 217 } 218 219 /* compare response packet to expected response */ 220 diff = psn_compare(pkt->psn, qp->comp.psn); 221 if (diff < 0) { 222 /* response is most likely a retried packet if it matches an 223 * uncompleted WQE go complete it else ignore it 224 */ 225 if (pkt->psn == wqe->last_psn) 226 return COMPST_COMP_ACK; 227 else 228 return COMPST_DONE; 229 } else if ((diff > 0) && (wqe->mask & WR_ATOMIC_OR_READ_MASK)) { 230 return COMPST_DONE; 231 } else { 232 return COMPST_CHECK_ACK; 233 } 234 } 235 236 static inline enum comp_state check_ack(struct rxe_qp *qp, 237 struct rxe_pkt_info *pkt, 238 struct rxe_send_wqe *wqe) 239 { 240 unsigned int mask = pkt->mask; 241 u8 syn; 242 struct rxe_dev *rxe = to_rdev(qp->ibqp.device); 243 244 /* Check the sequence only */ 245 switch (qp->comp.opcode) { 246 case -1: 247 /* Will catch all *_ONLY cases. */ 248 if (!(mask & RXE_START_MASK)) 249 return COMPST_ERROR; 250 251 break; 252 253 case IB_OPCODE_RC_RDMA_READ_RESPONSE_FIRST: 254 case IB_OPCODE_RC_RDMA_READ_RESPONSE_MIDDLE: 255 if (pkt->opcode != IB_OPCODE_RC_RDMA_READ_RESPONSE_MIDDLE && 256 pkt->opcode != IB_OPCODE_RC_RDMA_READ_RESPONSE_LAST) { 257 /* read retries of partial data may restart from 258 * read response first or response only. 259 */ 260 if ((pkt->psn == wqe->first_psn && 261 pkt->opcode == 262 IB_OPCODE_RC_RDMA_READ_RESPONSE_FIRST) || 263 (wqe->first_psn == wqe->last_psn && 264 pkt->opcode == 265 IB_OPCODE_RC_RDMA_READ_RESPONSE_ONLY)) 266 break; 267 268 return COMPST_ERROR; 269 } 270 break; 271 default: 272 WARN_ON_ONCE(1); 273 } 274 275 /* Check operation validity. */ 276 switch (pkt->opcode) { 277 case IB_OPCODE_RC_RDMA_READ_RESPONSE_FIRST: 278 case IB_OPCODE_RC_RDMA_READ_RESPONSE_LAST: 279 case IB_OPCODE_RC_RDMA_READ_RESPONSE_ONLY: 280 syn = aeth_syn(pkt); 281 282 if ((syn & AETH_TYPE_MASK) != AETH_ACK) 283 return COMPST_ERROR; 284 285 /* fall through */ 286 /* (IB_OPCODE_RC_RDMA_READ_RESPONSE_MIDDLE doesn't have an AETH) 287 */ 288 case IB_OPCODE_RC_RDMA_READ_RESPONSE_MIDDLE: 289 if (wqe->wr.opcode != IB_WR_RDMA_READ && 290 wqe->wr.opcode != IB_WR_RDMA_READ_WITH_INV) { 291 wqe->status = IB_WC_FATAL_ERR; 292 return COMPST_ERROR; 293 } 294 reset_retry_counters(qp); 295 return COMPST_READ; 296 297 case IB_OPCODE_RC_ATOMIC_ACKNOWLEDGE: 298 syn = aeth_syn(pkt); 299 300 if ((syn & AETH_TYPE_MASK) != AETH_ACK) 301 return COMPST_ERROR; 302 303 if (wqe->wr.opcode != IB_WR_ATOMIC_CMP_AND_SWP && 304 wqe->wr.opcode != IB_WR_ATOMIC_FETCH_AND_ADD) 305 return COMPST_ERROR; 306 reset_retry_counters(qp); 307 return COMPST_ATOMIC; 308 309 case IB_OPCODE_RC_ACKNOWLEDGE: 310 syn = aeth_syn(pkt); 311 switch (syn & AETH_TYPE_MASK) { 312 case AETH_ACK: 313 reset_retry_counters(qp); 314 return COMPST_WRITE_SEND; 315 316 case AETH_RNR_NAK: 317 rxe_counter_inc(rxe, RXE_CNT_RCV_RNR); 318 return COMPST_RNR_RETRY; 319 320 case AETH_NAK: 321 switch (syn) { 322 case AETH_NAK_PSN_SEQ_ERROR: 323 /* a nak implicitly acks all packets with psns 324 * before 325 */ 326 if (psn_compare(pkt->psn, qp->comp.psn) > 0) { 327 rxe_counter_inc(rxe, 328 RXE_CNT_RCV_SEQ_ERR); 329 qp->comp.psn = pkt->psn; 330 if (qp->req.wait_psn) { 331 qp->req.wait_psn = 0; 332 rxe_run_task(&qp->req.task, 1); 333 } 334 } 335 return COMPST_ERROR_RETRY; 336 337 case AETH_NAK_INVALID_REQ: 338 wqe->status = IB_WC_REM_INV_REQ_ERR; 339 return COMPST_ERROR; 340 341 case AETH_NAK_REM_ACC_ERR: 342 wqe->status = IB_WC_REM_ACCESS_ERR; 343 return COMPST_ERROR; 344 345 case AETH_NAK_REM_OP_ERR: 346 wqe->status = IB_WC_REM_OP_ERR; 347 return COMPST_ERROR; 348 349 default: 350 pr_warn("unexpected nak %x\n", syn); 351 wqe->status = IB_WC_REM_OP_ERR; 352 return COMPST_ERROR; 353 } 354 355 default: 356 return COMPST_ERROR; 357 } 358 break; 359 360 default: 361 pr_warn("unexpected opcode\n"); 362 } 363 364 return COMPST_ERROR; 365 } 366 367 static inline enum comp_state do_read(struct rxe_qp *qp, 368 struct rxe_pkt_info *pkt, 369 struct rxe_send_wqe *wqe) 370 { 371 int ret; 372 373 ret = copy_data(qp->pd, IB_ACCESS_LOCAL_WRITE, 374 &wqe->dma, payload_addr(pkt), 375 payload_size(pkt), to_mem_obj, NULL); 376 if (ret) 377 return COMPST_ERROR; 378 379 if (wqe->dma.resid == 0 && (pkt->mask & RXE_END_MASK)) 380 return COMPST_COMP_ACK; 381 else 382 return COMPST_UPDATE_COMP; 383 } 384 385 static inline enum comp_state do_atomic(struct rxe_qp *qp, 386 struct rxe_pkt_info *pkt, 387 struct rxe_send_wqe *wqe) 388 { 389 int ret; 390 391 u64 atomic_orig = atmack_orig(pkt); 392 393 ret = copy_data(qp->pd, IB_ACCESS_LOCAL_WRITE, 394 &wqe->dma, &atomic_orig, 395 sizeof(u64), to_mem_obj, NULL); 396 if (ret) 397 return COMPST_ERROR; 398 else 399 return COMPST_COMP_ACK; 400 } 401 402 static void make_send_cqe(struct rxe_qp *qp, struct rxe_send_wqe *wqe, 403 struct rxe_cqe *cqe) 404 { 405 memset(cqe, 0, sizeof(*cqe)); 406 407 if (!qp->is_user) { 408 struct ib_wc *wc = &cqe->ibwc; 409 410 wc->wr_id = wqe->wr.wr_id; 411 wc->status = wqe->status; 412 wc->opcode = wr_to_wc_opcode(wqe->wr.opcode); 413 if (wqe->wr.opcode == IB_WR_RDMA_WRITE_WITH_IMM || 414 wqe->wr.opcode == IB_WR_SEND_WITH_IMM) 415 wc->wc_flags = IB_WC_WITH_IMM; 416 wc->byte_len = wqe->dma.length; 417 wc->qp = &qp->ibqp; 418 } else { 419 struct ib_uverbs_wc *uwc = &cqe->uibwc; 420 421 uwc->wr_id = wqe->wr.wr_id; 422 uwc->status = wqe->status; 423 uwc->opcode = wr_to_wc_opcode(wqe->wr.opcode); 424 if (wqe->wr.opcode == IB_WR_RDMA_WRITE_WITH_IMM || 425 wqe->wr.opcode == IB_WR_SEND_WITH_IMM) 426 uwc->wc_flags = IB_WC_WITH_IMM; 427 uwc->byte_len = wqe->dma.length; 428 uwc->qp_num = qp->ibqp.qp_num; 429 } 430 } 431 432 /* 433 * IBA Spec. Section 10.7.3.1 SIGNALED COMPLETIONS 434 * ---------8<---------8<------------- 435 * ...Note that if a completion error occurs, a Work Completion 436 * will always be generated, even if the signaling 437 * indicator requests an Unsignaled Completion. 438 * ---------8<---------8<------------- 439 */ 440 static void do_complete(struct rxe_qp *qp, struct rxe_send_wqe *wqe) 441 { 442 struct rxe_dev *rxe = to_rdev(qp->ibqp.device); 443 struct rxe_cqe cqe; 444 445 if ((qp->sq_sig_type == IB_SIGNAL_ALL_WR) || 446 (wqe->wr.send_flags & IB_SEND_SIGNALED) || 447 wqe->status != IB_WC_SUCCESS) { 448 make_send_cqe(qp, wqe, &cqe); 449 advance_consumer(qp->sq.queue); 450 rxe_cq_post(qp->scq, &cqe, 0); 451 } else { 452 advance_consumer(qp->sq.queue); 453 } 454 455 if (wqe->wr.opcode == IB_WR_SEND || 456 wqe->wr.opcode == IB_WR_SEND_WITH_IMM || 457 wqe->wr.opcode == IB_WR_SEND_WITH_INV) 458 rxe_counter_inc(rxe, RXE_CNT_RDMA_SEND); 459 460 /* 461 * we completed something so let req run again 462 * if it is trying to fence 463 */ 464 if (qp->req.wait_fence) { 465 qp->req.wait_fence = 0; 466 rxe_run_task(&qp->req.task, 1); 467 } 468 } 469 470 static inline enum comp_state complete_ack(struct rxe_qp *qp, 471 struct rxe_pkt_info *pkt, 472 struct rxe_send_wqe *wqe) 473 { 474 unsigned long flags; 475 476 if (wqe->has_rd_atomic) { 477 wqe->has_rd_atomic = 0; 478 atomic_inc(&qp->req.rd_atomic); 479 if (qp->req.need_rd_atomic) { 480 qp->comp.timeout_retry = 0; 481 qp->req.need_rd_atomic = 0; 482 rxe_run_task(&qp->req.task, 1); 483 } 484 } 485 486 if (unlikely(qp->req.state == QP_STATE_DRAIN)) { 487 /* state_lock used by requester & completer */ 488 spin_lock_irqsave(&qp->state_lock, flags); 489 if ((qp->req.state == QP_STATE_DRAIN) && 490 (qp->comp.psn == qp->req.psn)) { 491 qp->req.state = QP_STATE_DRAINED; 492 spin_unlock_irqrestore(&qp->state_lock, flags); 493 494 if (qp->ibqp.event_handler) { 495 struct ib_event ev; 496 497 ev.device = qp->ibqp.device; 498 ev.element.qp = &qp->ibqp; 499 ev.event = IB_EVENT_SQ_DRAINED; 500 qp->ibqp.event_handler(&ev, 501 qp->ibqp.qp_context); 502 } 503 } else { 504 spin_unlock_irqrestore(&qp->state_lock, flags); 505 } 506 } 507 508 do_complete(qp, wqe); 509 510 if (psn_compare(pkt->psn, qp->comp.psn) >= 0) 511 return COMPST_UPDATE_COMP; 512 else 513 return COMPST_DONE; 514 } 515 516 static inline enum comp_state complete_wqe(struct rxe_qp *qp, 517 struct rxe_pkt_info *pkt, 518 struct rxe_send_wqe *wqe) 519 { 520 if (pkt && wqe->state == wqe_state_pending) { 521 if (psn_compare(wqe->last_psn, qp->comp.psn) >= 0) { 522 qp->comp.psn = (wqe->last_psn + 1) & BTH_PSN_MASK; 523 qp->comp.opcode = -1; 524 } 525 526 if (qp->req.wait_psn) { 527 qp->req.wait_psn = 0; 528 rxe_run_task(&qp->req.task, 1); 529 } 530 } 531 532 do_complete(qp, wqe); 533 534 return COMPST_GET_WQE; 535 } 536 537 static void rxe_drain_resp_pkts(struct rxe_qp *qp, bool notify) 538 { 539 struct sk_buff *skb; 540 struct rxe_send_wqe *wqe; 541 542 while ((skb = skb_dequeue(&qp->resp_pkts))) { 543 rxe_drop_ref(qp); 544 kfree_skb(skb); 545 } 546 547 while ((wqe = queue_head(qp->sq.queue))) { 548 if (notify) { 549 wqe->status = IB_WC_WR_FLUSH_ERR; 550 do_complete(qp, wqe); 551 } else { 552 advance_consumer(qp->sq.queue); 553 } 554 } 555 } 556 557 int rxe_completer(void *arg) 558 { 559 struct rxe_qp *qp = (struct rxe_qp *)arg; 560 struct rxe_dev *rxe = to_rdev(qp->ibqp.device); 561 struct rxe_send_wqe *wqe = wqe; 562 struct sk_buff *skb = NULL; 563 struct rxe_pkt_info *pkt = NULL; 564 enum comp_state state; 565 566 rxe_add_ref(qp); 567 568 if (!qp->valid || qp->req.state == QP_STATE_ERROR || 569 qp->req.state == QP_STATE_RESET) { 570 rxe_drain_resp_pkts(qp, qp->valid && 571 qp->req.state == QP_STATE_ERROR); 572 goto exit; 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 goto exit; 584 585 state = COMPST_GET_ACK; 586 587 while (1) { 588 pr_debug("qp#%d state = %s\n", qp_num(qp), 589 comp_state_name[state]); 590 switch (state) { 591 case COMPST_GET_ACK: 592 skb = skb_dequeue(&qp->resp_pkts); 593 if (skb) { 594 pkt = SKB_TO_PKT(skb); 595 qp->comp.timeout_retry = 0; 596 } 597 state = COMPST_GET_WQE; 598 break; 599 600 case COMPST_GET_WQE: 601 state = get_wqe(qp, pkt, &wqe); 602 break; 603 604 case COMPST_CHECK_PSN: 605 state = check_psn(qp, pkt, wqe); 606 break; 607 608 case COMPST_CHECK_ACK: 609 state = check_ack(qp, pkt, wqe); 610 break; 611 612 case COMPST_READ: 613 state = do_read(qp, pkt, wqe); 614 break; 615 616 case COMPST_ATOMIC: 617 state = do_atomic(qp, pkt, wqe); 618 break; 619 620 case COMPST_WRITE_SEND: 621 if (wqe->state == wqe_state_pending && 622 wqe->last_psn == pkt->psn) 623 state = COMPST_COMP_ACK; 624 else 625 state = COMPST_UPDATE_COMP; 626 break; 627 628 case COMPST_COMP_ACK: 629 state = complete_ack(qp, pkt, wqe); 630 break; 631 632 case COMPST_COMP_WQE: 633 state = complete_wqe(qp, pkt, wqe); 634 break; 635 636 case COMPST_UPDATE_COMP: 637 if (pkt->mask & RXE_END_MASK) 638 qp->comp.opcode = -1; 639 else 640 qp->comp.opcode = pkt->opcode; 641 642 if (psn_compare(pkt->psn, qp->comp.psn) >= 0) 643 qp->comp.psn = (pkt->psn + 1) & BTH_PSN_MASK; 644 645 if (qp->req.wait_psn) { 646 qp->req.wait_psn = 0; 647 rxe_run_task(&qp->req.task, 1); 648 } 649 650 state = COMPST_DONE; 651 break; 652 653 case COMPST_DONE: 654 if (pkt) { 655 rxe_drop_ref(pkt->qp); 656 kfree_skb(skb); 657 skb = NULL; 658 } 659 goto done; 660 661 case COMPST_EXIT: 662 if (qp->comp.timeout_retry && wqe) { 663 state = COMPST_ERROR_RETRY; 664 break; 665 } 666 667 /* re reset the timeout counter if 668 * (1) QP is type RC 669 * (2) the QP is alive 670 * (3) there is a packet sent by the requester that 671 * might be acked (we still might get spurious 672 * timeouts but try to keep them as few as possible) 673 * (4) the timeout parameter is set 674 */ 675 if ((qp_type(qp) == IB_QPT_RC) && 676 (qp->req.state == QP_STATE_READY) && 677 (psn_compare(qp->req.psn, qp->comp.psn) > 0) && 678 qp->qp_timeout_jiffies) 679 mod_timer(&qp->retrans_timer, 680 jiffies + qp->qp_timeout_jiffies); 681 goto exit; 682 683 case COMPST_ERROR_RETRY: 684 /* we come here if the retry timer fired and we did 685 * not receive a response packet. try to retry the send 686 * queue if that makes sense and the limits have not 687 * been exceeded. remember that some timeouts are 688 * spurious since we do not reset the timer but kick 689 * it down the road or let it expire 690 */ 691 692 /* there is nothing to retry in this case */ 693 if (!wqe || (wqe->state == wqe_state_posted)) { 694 goto exit; 695 } 696 697 /* if we've started a retry, don't start another 698 * retry sequence, unless this is a timeout. 699 */ 700 if (qp->comp.started_retry && 701 !qp->comp.timeout_retry) { 702 if (pkt) { 703 rxe_drop_ref(pkt->qp); 704 kfree_skb(skb); 705 skb = NULL; 706 } 707 708 goto done; 709 } 710 711 if (qp->comp.retry_cnt > 0) { 712 if (qp->comp.retry_cnt != 7) 713 qp->comp.retry_cnt--; 714 715 /* no point in retrying if we have already 716 * seen the last ack that the requester could 717 * have caused 718 */ 719 if (psn_compare(qp->req.psn, 720 qp->comp.psn) > 0) { 721 /* tell the requester to retry the 722 * send queue next time around 723 */ 724 rxe_counter_inc(rxe, 725 RXE_CNT_COMP_RETRY); 726 qp->req.need_retry = 1; 727 qp->comp.started_retry = 1; 728 rxe_run_task(&qp->req.task, 1); 729 } 730 731 if (pkt) { 732 rxe_drop_ref(pkt->qp); 733 kfree_skb(skb); 734 skb = NULL; 735 } 736 737 goto done; 738 739 } else { 740 rxe_counter_inc(rxe, RXE_CNT_RETRY_EXCEEDED); 741 wqe->status = IB_WC_RETRY_EXC_ERR; 742 state = COMPST_ERROR; 743 } 744 break; 745 746 case COMPST_RNR_RETRY: 747 if (qp->comp.rnr_retry > 0) { 748 if (qp->comp.rnr_retry != 7) 749 qp->comp.rnr_retry--; 750 751 qp->req.need_retry = 1; 752 pr_debug("qp#%d set rnr nak timer\n", 753 qp_num(qp)); 754 mod_timer(&qp->rnr_nak_timer, 755 jiffies + rnrnak_jiffies(aeth_syn(pkt) 756 & ~AETH_TYPE_MASK)); 757 rxe_drop_ref(pkt->qp); 758 kfree_skb(skb); 759 skb = NULL; 760 goto exit; 761 } else { 762 rxe_counter_inc(rxe, 763 RXE_CNT_RNR_RETRY_EXCEEDED); 764 wqe->status = IB_WC_RNR_RETRY_EXC_ERR; 765 state = COMPST_ERROR; 766 } 767 break; 768 769 case COMPST_ERROR: 770 WARN_ON_ONCE(wqe->status == IB_WC_SUCCESS); 771 do_complete(qp, wqe); 772 rxe_qp_error(qp); 773 774 if (pkt) { 775 rxe_drop_ref(pkt->qp); 776 kfree_skb(skb); 777 skb = NULL; 778 } 779 780 goto exit; 781 } 782 } 783 784 exit: 785 /* we come here if we are done with processing and want the task to 786 * exit from the loop calling us 787 */ 788 WARN_ON_ONCE(skb); 789 rxe_drop_ref(qp); 790 return -EAGAIN; 791 792 done: 793 /* we come here if we have processed a packet we want the task to call 794 * us again to see if there is anything else to do 795 */ 796 WARN_ON_ONCE(skb); 797 rxe_drop_ref(qp); 798 return 0; 799 } 800