From a0b34f75ec209e40f06912380533ec525691544f Mon Sep 17 00:00:00 2001 From: Kaike Wan Date: Thu, 24 Jan 2019 06:36:48 -0800 Subject: IB/hfi1: Add interlock between a TID RDMA request and other requests This locking mechanism is designed to provent vavious memory corruption scenarios from occurring when requests are pipelined, especially when RDMA READ/WRITE requests are interleaved with TID RDMA READ/WRITE requests: 1. READ-AFTER-READ; 2. READ-AFTER-WRITE; 3. WRITE-AFTER-READ; When memory corruption is likely, a request will be held back until previous requests have been completed. Reviewed-by: Mike Marciniszyn Signed-off-by: Mitko Haralanov Signed-off-by: Kaike Wan Signed-off-by: Dennis Dalessandro Signed-off-by: Doug Ledford --- drivers/infiniband/hw/hfi1/rc.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) (limited to 'drivers/infiniband/hw/hfi1/rc.c') diff --git a/drivers/infiniband/hw/hfi1/rc.c b/drivers/infiniband/hw/hfi1/rc.c index a5aacf8e5b93..349751cb8b47 100644 --- a/drivers/infiniband/hw/hfi1/rc.c +++ b/drivers/infiniband/hw/hfi1/rc.c @@ -482,6 +482,15 @@ check_s_state: len = wqe->length; ss = &qp->s_sge; bth2 = mask_psn(qp->s_psn); + + /* + * Interlock between various IB requests and TID RDMA + * if necessary. + */ + if ((priv->s_flags & HFI1_S_TID_WAIT_INTERLCK) || + hfi1_tid_rdma_wqe_interlock(qp, wqe)) + goto bail; + switch (wqe->wr.opcode) { case IB_WR_SEND: case IB_WR_SEND_WITH_IMM: @@ -1321,6 +1330,7 @@ static void reset_psn(struct rvt_qp *qp, u32 psn) qp->s_state = OP(SEND_LAST); } done: + priv->s_flags &= ~HFI1_S_TID_WAIT_INTERLCK; qp->s_psn = psn; /* * Set RVT_S_WAIT_PSN as rc_complete() may start the timer @@ -1540,6 +1550,8 @@ struct rvt_swqe *do_rc_completion(struct rvt_qp *qp, struct rvt_swqe *wqe, struct hfi1_ibport *ibp) { + struct hfi1_qp_priv *priv = qp->priv; + lockdep_assert_held(&qp->s_lock); /* * Don't decrement refcount and don't generate a @@ -1608,6 +1620,10 @@ struct rvt_swqe *do_rc_completion(struct rvt_qp *qp, qp->s_draining = 0; wqe = rvt_get_swqe_ptr(qp, qp->s_acked); } + if (priv->s_flags & HFI1_S_TID_WAIT_INTERLCK) { + priv->s_flags &= ~HFI1_S_TID_WAIT_INTERLCK; + hfi1_schedule_send(qp); + } return wqe; } -- cgit v1.2.3-59-g8ed1b