// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB /* * Copyright (c) 2016 Mellanox Technologies Ltd. All rights reserved. * Copyright (c) 2015 System Fabric Works, Inc. All rights reserved. */ #include #include "rxe.h" #include "rxe_loc.h" #include "rxe_queue.h" #include "rxe_task.h" enum comp_state { COMPST_GET_ACK, COMPST_GET_WQE, COMPST_COMP_WQE, COMPST_COMP_ACK, COMPST_CHECK_PSN, COMPST_CHECK_ACK, COMPST_READ, COMPST_ATOMIC, COMPST_WRITE_SEND, COMPST_UPDATE_COMP, COMPST_ERROR_RETRY, COMPST_RNR_RETRY, COMPST_ERROR, COMPST_EXIT, /* We have an issue, and we want to rerun the completer */ COMPST_DONE, /* The completer finished successflly */ }; static char *comp_state_name[] = { [COMPST_GET_ACK] = "GET ACK", [COMPST_GET_WQE] = "GET WQE", [COMPST_COMP_WQE] = "COMP WQE", [COMPST_COMP_ACK] = "COMP ACK", [COMPST_CHECK_PSN] = "CHECK PSN", [COMPST_CHECK_ACK] = "CHECK ACK", [COMPST_READ] = "READ", [COMPST_ATOMIC] = "ATOMIC", [COMPST_WRITE_SEND] = "WRITE/SEND", [COMPST_UPDATE_COMP] = "UPDATE COMP", [COMPST_ERROR_RETRY] = "ERROR RETRY", [COMPST_RNR_RETRY] = "RNR RETRY", [COMPST_ERROR] = "ERROR", [COMPST_EXIT] = "EXIT", [COMPST_DONE] = "DONE", }; static unsigned long rnrnak_usec[32] = { [IB_RNR_TIMER_655_36] = 655360, [IB_RNR_TIMER_000_01] = 10, [IB_RNR_TIMER_000_02] = 20, [IB_RNR_TIMER_000_03] = 30, [IB_RNR_TIMER_000_04] = 40, [IB_RNR_TIMER_000_06] = 60, [IB_RNR_TIMER_000_08] = 80, [IB_RNR_TIMER_000_12] = 120, [IB_RNR_TIMER_000_16] = 160, [IB_RNR_TIMER_000_24] = 240, [IB_RNR_TIMER_000_32] = 320, [IB_RNR_TIMER_000_48] = 480, [IB_RNR_TIMER_000_64] = 640, [IB_RNR_TIMER_000_96] = 960, [IB_RNR_TIMER_001_28] = 1280, [IB_RNR_TIMER_001_92] = 1920, [IB_RNR_TIMER_002_56] = 2560, [IB_RNR_TIMER_003_84] = 3840, [IB_RNR_TIMER_005_12] = 5120, [IB_RNR_TIMER_007_68] = 7680, [IB_RNR_TIMER_010_24] = 10240, [IB_RNR_TIMER_015_36] = 15360, [IB_RNR_TIMER_020_48] = 20480, [IB_RNR_TIMER_030_72] = 30720, [IB_RNR_TIMER_040_96] = 40960, [IB_RNR_TIMER_061_44] = 61410, [IB_RNR_TIMER_081_92] = 81920, [IB_RNR_TIMER_122_88] = 122880, [IB_RNR_TIMER_163_84] = 163840, [IB_RNR_TIMER_245_76] = 245760, [IB_RNR_TIMER_327_68] = 327680, [IB_RNR_TIMER_491_52] = 491520, }; static inline unsigned long rnrnak_jiffies(u8 timeout) { return max_t(unsigned long, usecs_to_jiffies(rnrnak_usec[timeout]), 1); } static enum ib_wc_opcode wr_to_wc_opcode(enum ib_wr_opcode opcode) { switch (opcode) { case IB_WR_RDMA_WRITE: return IB_WC_RDMA_WRITE; case IB_WR_RDMA_WRITE_WITH_IMM: return IB_WC_RDMA_WRITE; case IB_WR_SEND: return IB_WC_SEND; case IB_WR_SEND_WITH_IMM: return IB_WC_SEND; case IB_WR_RDMA_READ: return IB_WC_RDMA_READ; case IB_WR_ATOMIC_CMP_AND_SWP: return IB_WC_COMP_SWAP; case IB_WR_ATOMIC_FETCH_AND_ADD: return IB_WC_FETCH_ADD; case IB_WR_LSO: return IB_WC_LSO; case IB_WR_SEND_WITH_INV: return IB_WC_SEND; case IB_WR_RDMA_READ_WITH_INV: return IB_WC_RDMA_READ; case IB_WR_LOCAL_INV: return IB_WC_LOCAL_INV; case IB_WR_REG_MR: return IB_WC_REG_MR; case IB_WR_BIND_MW: return IB_WC_BIND_MW; case IB_WR_ATOMIC_WRITE: return IB_WC_ATOMIC_WRITE; case IB_WR_FLUSH: return IB_WC_FLUSH; default: return 0xff; } } void retransmit_timer(struct timer_list *t) { struct rxe_qp *qp = from_timer(qp, t, retrans_timer); unsigned long flags; rxe_dbg_qp(qp, "retransmit timer fired\n"); spin_lock_irqsave(&qp->state_lock, flags); if (qp->valid) { qp->comp.timeout = 1; rxe_sched_task(&qp->comp.task); } spin_unlock_irqrestore(&qp->state_lock, flags); } void rxe_comp_queue_pkt(struct rxe_qp *qp, struct sk_buff *skb) { int must_sched; skb_queue_tail(&qp->resp_pkts, skb); must_sched = skb_queue_len(&qp->resp_pkts) > 1; if (must_sched != 0) rxe_counter_inc(SKB_TO_PKT(skb)->rxe, RXE_CNT_COMPLETER_SCHED); if (must_sched) rxe_sched_task(&qp->comp.task); else rxe_run_task(&qp->comp.task); } static inline enum comp_state get_wqe(struct rxe_qp *qp, struct rxe_pkt_info *pkt, struct rxe_send_wqe **wqe_p) { struct rxe_send_wqe *wqe; /* we come here whether or not we found a response packet to see if * there are any posted WQEs */ wqe = queue_head(qp->sq.queue, QUEUE_TYPE_FROM_CLIENT); *wqe_p = wqe; /* no WQE or requester has not started it yet */ if (!wqe || wqe->state == wqe_state_posted) return pkt ? COMPST_DONE : COMPST_EXIT; /* WQE does not require an ack */ if (wqe->state == wqe_state_done) return COMPST_COMP_WQE; /* WQE caused an error */ if (wqe->state == wqe_state_error) return COMPST_ERROR; /* we have a WQE, if we also have an ack check its PSN */ return pkt ? COMPST_CHECK_PSN : COMPST_EXIT; } static inline void reset_retry_counters(struct rxe_qp *qp) { qp->comp.retry_cnt = qp->attr.retry_cnt; qp->comp.rnr_retry = qp->attr.rnr_retry; qp->comp.started_retry = 0; } static inline enum comp_state check_psn(struct rxe_qp *qp, struct rxe_pkt_info *pkt, struct rxe_send_wqe *wqe) { s32 diff; /* check to see if response is past the oldest WQE. if it is, complete * send/write or error read/atomic */ diff = psn_compare(pkt->psn, wqe->last_psn); if (diff > 0) { if (wqe->state == wqe_state_pending) { if (wqe->mask & WR_ATOMIC_OR_READ_MASK) return COMPST_ERROR_RETRY; reset_retry_counters(qp); return COMPST_COMP_WQE; } else { return COMPST_DONE; } } /* compare response packet to expected response */ diff = psn_compare(pkt->psn, qp->comp.psn); if (diff < 0) { /* response is most likely a retried packet if it matches an * uncompleted WQE go complete it else ignore it */ if (pkt->psn == wqe->last_psn) return COMPST_COMP_ACK; else if (pkt->opcode == IB_OPCODE_RC_ACKNOWLEDGE && (qp->comp.opcode == IB_OPCODE_RC_RDMA_READ_RESPONSE_FIRST || qp->comp.opcode == IB_OPCODE_RC_RDMA_READ_RESPONSE_MIDDLE)) return COMPST_CHECK_ACK; else return COMPST_DONE; } else if ((diff > 0) && (wqe->mask & WR_ATOMIC_OR_READ_MASK)) { return COMPST_DONE; } else { return COMPST_CHECK_ACK; } } static inline enum comp_state check_ack(struct rxe_qp *qp, struct rxe_pkt_info *pkt, struct rxe_send_wqe *wqe) { unsigned int mask = pkt->mask; u8 syn; struct rxe_dev *rxe = to_rdev(qp->ibqp.device); /* Check the sequence only */ switch (qp->comp.opcode) { case -1: /* Will catch all *_ONLY cases. */ if (!(mask & RXE_START_MASK)) return COMPST_ERROR; break; case IB_OPCODE_RC_RDMA_READ_RESPONSE_FIRST: case IB_OPCODE_RC_RDMA_READ_RESPONSE_MIDDLE: /* Check NAK code to handle a remote error */ if (pkt->opcode == IB_OPCODE_RC_ACKNOWLEDGE) break; if (pkt->opcode != IB_OPCODE_RC_RDMA_READ_RESPONSE_MIDDLE && pkt->opcode != IB_OPCODE_RC_RDMA_READ_RESPONSE_LAST) { /* read retries of partial data may restart from * read response first or response only. */ if ((pkt->psn == wqe->first_psn && pkt->opcode == IB_OPCODE_RC_RDMA_READ_RESPONSE_FIRST) || (wqe->first_psn == wqe->last_psn && pkt->opcode == IB_OPCODE_RC_RDMA_READ_RESPONSE_ONLY)) break; return COMPST_ERROR; } break; default: WARN_ON_ONCE(1); } /* Check operation validity. */ switch (pkt->opcode) { case IB_OPCODE_RC_RDMA_READ_RESPONSE_FIRST: case IB_OPCODE_RC_RDMA_READ_RESPONSE_LAST: case IB_OPCODE_RC_RDMA_READ_RESPONSE_ONLY: syn = aeth_syn(pkt); if ((syn & AETH_TYPE_MASK) != AETH_ACK) return COMPST_ERROR; if (wqe->wr.opcode == IB_WR_ATOMIC_WRITE) return COMPST_WRITE_SEND; fallthrough; /* (IB_OPCODE_RC_RDMA_READ_RESPONSE_MIDDLE doesn't have an AETH) */ case IB_OPCODE_RC_RDMA_READ_RESPONSE_MIDDLE: if (wqe->wr.opcode != IB_WR_RDMA_READ && wqe->wr.opcode != IB_WR_RDMA_READ_WITH_INV && wqe->wr.opcode != IB_WR_FLUSH) { wqe->status = IB_WC_FATAL_ERR; return COMPST_ERROR; } reset_retry_counters(qp); return COMPST_READ; case IB_OPCODE_RC_ATOMIC_ACKNOWLEDGE: syn = aeth_syn(pkt); if ((syn & AETH_TYPE_MASK) != AETH_ACK) return COMPST_ERROR; if (wqe->wr.opcode != IB_WR_ATOMIC_CMP_AND_SWP && wqe->wr.opcode != IB_WR_ATOMIC_FETCH_AND_ADD) return COMPST_ERROR; reset_retry_counters(qp); return COMPST_ATOMIC; case IB_OPCODE_RC_ACKNOWLEDGE: syn = aeth_syn(pkt); switch (syn & AETH_TYPE_MASK) { case AETH_ACK: reset_retry_counters(qp); return COMPST_WRITE_SEND; case AETH_RNR_NAK: rxe_counter_inc(rxe, RXE_CNT_RCV_RNR); return COMPST_RNR_RETRY; case AETH_NAK: switch (syn) { case AETH_NAK_PSN_SEQ_ERROR: /* a nak implicitly acks all packets with psns * before */ if (psn_compare(pkt->psn, qp->comp.psn) > 0) { rxe_counter_inc(rxe, RXE_CNT_RCV_SEQ_ERR); qp->comp.psn = pkt->psn; if (qp->req.wait_psn) { qp->req.wait_psn = 0; rxe_sched_task(&qp->req.task); } } return COMPST_ERROR_RETRY; case AETH_NAK_INVALID_REQ: wqe->status = IB_WC_REM_INV_REQ_ERR; return COMPST_ERROR; case AETH_NAK_REM_ACC_ERR: wqe->status = IB_WC_REM_ACCESS_ERR; return COMPST_ERROR; case AETH_NAK_REM_OP_ERR: wqe->status = IB_WC_REM_OP_ERR; return COMPST_ERROR; default: rxe_dbg_qp(qp, "unexpected nak %x\n", syn); wqe->status = IB_WC_REM_OP_ERR; return COMPST_ERROR; } default: return COMPST_ERROR; } break; default: rxe_dbg_qp(qp, "unexpected opcode\n"); } return COMPST_ERROR; } static inline enum comp_state do_read(struct rxe_qp *qp, struct rxe_pkt_info *pkt, struct rxe_send_wqe *wqe) { int ret; ret = copy_data(qp->pd, IB_ACCESS_LOCAL_WRITE, &wqe->dma, payload_addr(pkt), payload_size(pkt), RXE_TO_MR_OBJ); if (ret) { wqe->status = IB_WC_LOC_PROT_ERR; return COMPST_ERROR; } if (wqe->dma.resid == 0 && (pkt->mask & RXE_END_MASK)) return COMPST_COMP_ACK; return COMPST_UPDATE_COMP; } static inline enum comp_state do_atomic(struct rxe_qp *qp, struct rxe_pkt_info *pkt, struct rxe_send_wqe *wqe) { int ret; u64 atomic_orig = atmack_orig(pkt); ret = copy_data(qp->pd, IB_ACCESS_LOCAL_WRITE, &wqe->dma, &atomic_orig, sizeof(u64), RXE_TO_MR_OBJ); if (ret) { wqe->status = IB_WC_LOC_PROT_ERR; return COMPST_ERROR; } return COMPST_COMP_ACK; } static void make_send_cqe(struct rxe_qp *qp, struct rxe_send_wqe *wqe, struct rxe_cqe *cqe) { struct ib_wc *wc = &cqe->ibwc; struct ib_uverbs_wc *uwc = &cqe->uibwc; memset(cqe, 0, sizeof(*cqe)); if (!qp->is_user) { wc->wr_id = wqe->wr.wr_id; wc->status = wqe->status; wc->qp = &qp->ibqp; } else { uwc->wr_id = wqe->wr.wr_id; uwc->status = wqe->status; uwc->qp_num = qp->ibqp.qp_num; } if (wqe->status == IB_WC_SUCCESS) { if (!qp->is_user) { wc->opcode = wr_to_wc_opcode(wqe->wr.opcode); if (wqe->wr.opcode == IB_WR_RDMA_WRITE_WITH_IMM || wqe->wr.opcode == IB_WR_SEND_WITH_IMM) wc->wc_flags = IB_WC_WITH_IMM; wc->byte_len = wqe->dma.length; } else { uwc->opcode = wr_to_wc_opcode(wqe->wr.opcode); if (wqe->wr.opcode == IB_WR_RDMA_WRITE_WITH_IMM || wqe->wr.opcode == IB_WR_SEND_WITH_IMM) uwc->wc_flags = IB_WC_WITH_IMM; uwc->byte_len = wqe->dma.length; } } else { if (wqe->status != IB_WC_WR_FLUSH_ERR) rxe_err_qp(qp, "non-flush error status = %d", wqe->status); } } /* * IBA Spec. Section 10.7.3.1 SIGNALED COMPLETIONS * ---------8<---------8<------------- * ...Note that if a completion error occurs, a Work Completion * will always be generated, even if the signaling * indicator requests an Unsignaled Completion. * ---------8<---------8<------------- */ static void do_complete(struct rxe_qp *qp, struct rxe_send_wqe *wqe) { struct rxe_dev *rxe = to_rdev(qp->ibqp.device); struct rxe_cqe cqe; bool post; /* do we need to post a completion */ post = ((qp->sq_sig_type == IB_SIGNAL_ALL_WR) || (wqe->wr.send_flags & IB_SEND_SIGNALED) || wqe->status != IB_WC_SUCCESS); if (post) make_send_cqe(qp, wqe, &cqe); queue_advance_consumer(qp->sq.queue, QUEUE_TYPE_FROM_CLIENT); if (post) rxe_cq_post(qp->scq, &cqe, 0); if (wqe->wr.opcode == IB_WR_SEND || wqe->wr.opcode == IB_WR_SEND_WITH_IMM || wqe->wr.opcode == IB_WR_SEND_WITH_INV) rxe_counter_inc(rxe, RXE_CNT_RDMA_SEND); /* * we completed something so let req run again * if it is trying to fence */ if (qp->req.wait_fence) { qp->req.wait_fence = 0; rxe_sched_task(&qp->req.task); } } static void comp_check_sq_drain_done(struct rxe_qp *qp) { unsigned long flags; spin_lock_irqsave(&qp->state_lock, flags); if (unlikely(qp_state(qp) == IB_QPS_SQD)) { if (qp->attr.sq_draining && qp->comp.psn == qp->req.psn) { qp->attr.sq_draining = 0; spin_unlock_irqrestore(&qp->state_lock, flags); if (qp->ibqp.event_handler) { struct ib_event ev; ev.device = qp->ibqp.device; ev.element.qp = &qp->ibqp; ev.event = IB_EVENT_SQ_DRAINED; qp->ibqp.event_handler(&ev, qp->ibqp.qp_context); } return; } } spin_unlock_irqrestore(&qp->state_lock, flags); } static inline enum comp_state complete_ack(struct rxe_qp *qp, struct rxe_pkt_info *pkt, struct rxe_send_wqe *wqe) { if (wqe->has_rd_atomic) { wqe->has_rd_atomic = 0; atomic_inc(&qp->req.rd_atomic); if (qp->req.need_rd_atomic) { qp->comp.timeout_retry = 0; qp->req.need_rd_atomic = 0; rxe_sched_task(&qp->req.task); } } comp_check_sq_drain_done(qp); do_complete(qp, wqe); if (psn_compare(pkt->psn, qp->comp.psn) >= 0) return COMPST_UPDATE_COMP; else return COMPST_DONE; } static inline enum comp_state complete_wqe(struct rxe_qp *qp, struct rxe_pkt_info *pkt, struct rxe_send_wqe *wqe) { if (pkt && wqe->state == wqe_state_pending) { if (psn_compare(wqe->last_psn, qp->comp.psn) >= 0) { qp->comp.psn = (wqe->last_psn + 1) & BTH_PSN_MASK; qp->comp.opcode = -1; } if (qp->req.wait_psn) { qp->req.wait_psn = 0; rxe_sched_task(&qp->req.task); } } do_complete(qp, wqe); return COMPST_GET_WQE; } /* drain incoming response packet queue */ static void drain_resp_pkts(struct rxe_qp *qp) { struct sk_buff *skb; while ((skb = skb_dequeue(&qp->resp_pkts))) { rxe_put(qp); kfree_skb(skb); ib_device_put(qp->ibqp.device); } } /* complete send wqe with flush error */ static int flush_send_wqe(struct rxe_qp *qp, struct rxe_send_wqe *wqe) { struct rxe_cqe cqe = {}; struct ib_wc *wc = &cqe.ibwc; struct ib_uverbs_wc *uwc = &cqe.uibwc; int err; if (qp->is_user) { uwc->wr_id = wqe->wr.wr_id; uwc->status = IB_WC_WR_FLUSH_ERR; uwc->qp_num = qp->ibqp.qp_num; } else { wc->wr_id = wqe->wr.wr_id; wc->status = IB_WC_WR_FLUSH_ERR; wc->qp = &qp->ibqp; } err = rxe_cq_post(qp->scq, &cqe, 0); if (err) rxe_dbg_cq(qp->scq, "post cq failed, err = %d", err); return err; } /* drain and optionally complete the send queue * if unable to complete a wqe, i.e. cq is full, stop * completing and flush the remaining wqes */ static void flush_send_queue(struct rxe_qp *qp, bool notify) { struct rxe_send_wqe *wqe; struct rxe_queue *q = qp->sq.queue; int err; /* send queue never got created. nothing to do. */ if (!qp->sq.queue) return; while ((wqe = queue_head(q, q->type))) { if (notify) { err = flush_send_wqe(qp, wqe); if (err) notify = 0; } queue_advance_consumer(q, q->type); } } static void free_pkt(struct rxe_pkt_info *pkt) { struct sk_buff *skb = PKT_TO_SKB(pkt); struct rxe_qp *qp = pkt->qp; struct ib_device *dev = qp->ibqp.device; kfree_skb(skb); rxe_put(qp); ib_device_put(dev); } /* reset the retry timer if * - QP is type RC * - there is a packet sent by the requester that * might be acked (we still might get spurious * timeouts but try to keep them as few as possible) * - the timeout parameter is set * - the QP is alive */ static void reset_retry_timer(struct rxe_qp *qp) { unsigned long flags; if (qp_type(qp) == IB_QPT_RC && qp->qp_timeout_jiffies) { spin_lock_irqsave(&qp->state_lock, flags); if (qp_state(qp) >= IB_QPS_RTS && psn_compare(qp->req.psn, qp->comp.psn) > 0) mod_timer(&qp->retrans_timer, jiffies + qp->qp_timeout_jiffies); spin_unlock_irqrestore(&qp->state_lock, flags); } } int rxe_completer(struct rxe_qp *qp) { struct rxe_dev *rxe = to_rdev(qp->ibqp.device); struct rxe_send_wqe *wqe = NULL; struct sk_buff *skb = NULL; struct rxe_pkt_info *pkt = NULL; enum comp_state state; int ret; unsigned long flags; spin_lock_irqsave(&qp->state_lock, flags); if (!qp->valid || qp_state(qp) == IB_QPS_ERR || qp_state(qp) == IB_QPS_RESET) { bool notify = qp->valid && (qp_state(qp) == IB_QPS_ERR); drain_resp_pkts(qp); flush_send_queue(qp, notify); spin_unlock_irqrestore(&qp->state_lock, flags); goto exit; } spin_unlock_irqrestore(&qp->state_lock, flags); if (qp->comp.timeout) { qp->comp.timeout_retry = 1; qp->comp.timeout = 0; } else { qp->comp.timeout_retry = 0; } if (qp->req.need_retry) goto exit; state = COMPST_GET_ACK; while (1) { rxe_dbg_qp(qp, "state = %s\n", comp_state_name[state]); switch (state) { case COMPST_GET_ACK: skb = skb_dequeue(&qp->resp_pkts); if (skb) { pkt = SKB_TO_PKT(skb); qp->comp.timeout_retry = 0; } state = COMPST_GET_WQE; break; case COMPST_GET_WQE: state = get_wqe(qp, pkt, &wqe); break; case COMPST_CHECK_PSN: state = check_psn(qp, pkt, wqe); break; case COMPST_CHECK_ACK: state = check_ack(qp, pkt, wqe); break; case COMPST_READ: state = do_read(qp, pkt, wqe); break; case COMPST_ATOMIC: state = do_atomic(qp, pkt, wqe); break; case COMPST_WRITE_SEND: if (wqe->state == wqe_state_pending && wqe->last_psn == pkt->psn) state = COMPST_COMP_ACK; else state = COMPST_UPDATE_COMP; break; case COMPST_COMP_ACK: state = complete_ack(qp, pkt, wqe); break; case COMPST_COMP_WQE: state = complete_wqe(qp, pkt, wqe); break; case COMPST_UPDATE_COMP: if (pkt->mask & RXE_END_MASK) qp->comp.opcode = -1; else qp->comp.opcode = pkt->opcode; if (psn_compare(pkt->psn, qp->comp.psn) >= 0) qp->comp.psn = (pkt->psn + 1) & BTH_PSN_MASK; if (qp->req.wait_psn) { qp->req.wait_psn = 0; rxe_sched_task(&qp->req.task); } state = COMPST_DONE; break; case COMPST_DONE: goto done; case COMPST_EXIT: if (qp->comp.timeout_retry && wqe) { state = COMPST_ERROR_RETRY; break; } reset_retry_timer(qp); goto exit; case COMPST_ERROR_RETRY: /* we come here if the retry timer fired and we did * not receive a response packet. try to retry the send * queue if that makes sense and the limits have not * been exceeded. remember that some timeouts are * spurious since we do not reset the timer but kick * it down the road or let it expire */ /* there is nothing to retry in this case */ if (!wqe || (wqe->state == wqe_state_posted)) goto exit; /* if we've started a retry, don't start another * retry sequence, unless this is a timeout. */ if (qp->comp.started_retry && !qp->comp.timeout_retry) goto done; if (qp->comp.retry_cnt > 0) { if (qp->comp.retry_cnt != 7) qp->comp.retry_cnt--; /* no point in retrying if we have already * seen the last ack that the requester could * have caused */ if (psn_compare(qp->req.psn, qp->comp.psn) > 0) { /* tell the requester to retry the * send queue next time around */ rxe_counter_inc(rxe, RXE_CNT_COMP_RETRY); qp->req.need_retry = 1; qp->comp.started_retry = 1; rxe_sched_task(&qp->req.task); } goto done; } else { rxe_counter_inc(rxe, RXE_CNT_RETRY_EXCEEDED); wqe->status = IB_WC_RETRY_EXC_ERR; state = COMPST_ERROR; } break; case COMPST_RNR_RETRY: /* we come here if we received an RNR NAK */ if (qp->comp.rnr_retry > 0) { if (qp->comp.rnr_retry != 7) qp->comp.rnr_retry--; /* don't start a retry flow until the * rnr timer has fired */ qp->req.wait_for_rnr_timer = 1; rxe_dbg_qp(qp, "set rnr nak timer\n"); // TODO who protects from destroy_qp?? mod_timer(&qp->rnr_nak_timer, jiffies + rnrnak_jiffies(aeth_syn(pkt) & ~AETH_TYPE_MASK)); goto exit; } else { rxe_counter_inc(rxe, RXE_CNT_RNR_RETRY_EXCEEDED); wqe->status = IB_WC_RNR_RETRY_EXC_ERR; state = COMPST_ERROR; } break; case COMPST_ERROR: WARN_ON_ONCE(wqe->status == IB_WC_SUCCESS); do_complete(qp, wqe); rxe_qp_error(qp); goto exit; } } /* A non-zero return value will cause rxe_do_task to * exit its loop and end the work item. A zero return * will continue looping and return to rxe_completer */ done: ret = 0; goto out; exit: ret = -EAGAIN; out: if (pkt) free_pkt(pkt); return ret; }