diff --git a/drivers/infiniband/sw/rxe/rxe_req.c b/drivers/infiniband/sw/rxe/rxe_req.c index 33b2d9d77021..13a848a518e8 100644 --- a/drivers/infiniband/sw/rxe/rxe_req.c +++ b/drivers/infiniband/sw/rxe/rxe_req.c @@ -511,24 +511,21 @@ static int fill_packet(struct rxe_qp *qp, struct rxe_send_wqe *wqe, } static void update_wqe_state(struct rxe_qp *qp, - struct rxe_send_wqe *wqe, - struct rxe_pkt_info *pkt, - enum wqe_state *prev_state) + struct rxe_send_wqe *wqe, + struct rxe_pkt_info *pkt) { - enum wqe_state prev_state_ = wqe->state; - if (pkt->mask & RXE_END_MASK) { if (qp_type(qp) == IB_QPT_RC) wqe->state = wqe_state_pending; } else { wqe->state = wqe_state_processing; } - - *prev_state = prev_state_; } -static void update_state(struct rxe_qp *qp, struct rxe_send_wqe *wqe, - struct rxe_pkt_info *pkt, int payload) +static void update_wqe_psn(struct rxe_qp *qp, + struct rxe_send_wqe *wqe, + struct rxe_pkt_info *pkt, + int payload) { /* number of packets left to send including current one */ int num_pkt = (wqe->dma.resid + payload + qp->mtu - 1) / qp->mtu; @@ -546,10 +543,35 @@ static void update_state(struct rxe_qp *qp, struct rxe_send_wqe *wqe, qp->req.psn = (wqe->first_psn + num_pkt) & BTH_PSN_MASK; else qp->req.psn = (qp->req.psn + 1) & BTH_PSN_MASK; +} +static void save_state(struct rxe_send_wqe *wqe, + struct rxe_qp *qp, + struct rxe_send_wqe *rollback_wqe, + struct rxe_qp *rollback_qp) +{ + rollback_wqe->state = wqe->state; + rollback_wqe->first_psn = wqe->first_psn; + rollback_wqe->last_psn = wqe->last_psn; + rollback_qp->req.psn = qp->req.psn; +} + +static void rollback_state(struct rxe_send_wqe *wqe, + struct rxe_qp *qp, + struct rxe_send_wqe *rollback_wqe, + struct rxe_qp *rollback_qp) +{ + wqe->state = rollback_wqe->state; + wqe->first_psn = rollback_wqe->first_psn; + wqe->last_psn = rollback_wqe->last_psn; + qp->req.psn = rollback_qp->req.psn; +} + +static void update_state(struct rxe_qp *qp, struct rxe_send_wqe *wqe, + struct rxe_pkt_info *pkt, int payload) +{ qp->req.opcode = pkt->opcode; - if (pkt->mask & RXE_END_MASK) qp->req.wqe_index = next_index(qp->sq.queue, qp->req.wqe_index); @@ -571,7 +593,8 @@ int rxe_requester(void *arg) int mtu; int opcode; int ret; - enum wqe_state prev_state; + struct rxe_qp rollback_qp; + struct rxe_send_wqe rollback_wqe; next_wqe: if (unlikely(!qp->valid || qp->req.state == QP_STATE_ERROR)) @@ -688,13 +711,21 @@ next_wqe: goto err; } - update_wqe_state(qp, wqe, &pkt, &prev_state); + /* + * To prevent a race on wqe access between requester and completer, + * wqe members state and psn need to be set before calling + * rxe_xmit_packet(). + * Otherwise, completer might initiate an unjustified retry flow. + */ + save_state(wqe, qp, &rollback_wqe, &rollback_qp); + update_wqe_state(qp, wqe, &pkt); + update_wqe_psn(qp, wqe, &pkt, payload); ret = rxe_xmit_packet(to_rdev(qp->ibqp.device), qp, &pkt, skb); if (ret) { qp->need_req_skb = 1; kfree_skb(skb); - wqe->state = prev_state; + rollback_state(wqe, qp, &rollback_wqe, &rollback_qp); if (ret == -EAGAIN) { rxe_run_task(&qp->req.task, 1);