[PATCH rdma-next v3 05/10] RDMA/mana_ib: Post receive WRs on kernel RC QPs

[Konstantin Taranov <kotaranov@linux.microsoft.com>]

From: Konstantin Taranov <kotaranov@microsoft.com>

Implement receive request posting for RC QPs. When posting a batch of
WRs, ring the doorbell periodically to prevent the u8 counter from
overflowing.

Signed-off-by: Konstantin Taranov <kotaranov@microsoft.com>
---
 drivers/infiniband/hw/mana/wr.c | 37 +++++++++++++++++++++++++++++++++
 1 file changed, 37 insertions(+)

diff --git a/drivers/infiniband/hw/mana/wr.c b/drivers/infiniband/hw/mana/wr.c
index 250d673f58f2..5d42af91fce4 100644
--- a/drivers/infiniband/hw/mana/wr.c
+++ b/drivers/infiniband/hw/mana/wr.c
@@ -70,6 +70,41 @@ static int mana_ib_post_recv_ud(struct mana_ib_qp *qp, const struct ib_recv_wr *
 	return err;
 }
 
+static int mana_ib_post_recv_rc(struct mana_ib_qp *qp, const struct ib_recv_wr *wr,
+				const struct ib_recv_wr **bad_wr)
+{
+	struct mana_ib_dev *mdev = container_of(qp->ibqp.device, struct mana_ib_dev, ib_dev);
+	struct mana_ib_queue *ib_rq = mana_qp_get_rq(qp);
+	unsigned long flags;
+	u8 wqe_cnt = 0;
+	int err = 0;
+
+	spin_lock_irqsave(&qp->rq_lock, flags);
+
+	for (; wr; wr = wr->next) {
+		err = mana_ib_post_rq(qp, wr);
+		if (unlikely(err)) {
+			*bad_wr = wr;
+			break;
+		}
+		wqe_cnt++;
+		if (wqe_cnt == 0xFF) {
+			mana_gd_wq_ring_doorbell_ext(mdev_to_gc(mdev), ib_rq->kmem,
+						     ib_rq->kmem->head * GDMA_WQE_BU_SIZE,
+						     wqe_cnt, 0);
+			wqe_cnt = 0;
+		}
+	}
+
+	if (wqe_cnt)
+		mana_gd_wq_ring_doorbell_ext(mdev_to_gc(mdev), ib_rq->kmem,
+					     ib_rq->kmem->head * GDMA_WQE_BU_SIZE,
+					     wqe_cnt, 0);
+
+	spin_unlock_irqrestore(&qp->rq_lock, flags);
+	return err;
+}
+
 int mana_ib_post_recv(struct ib_qp *ibqp, const struct ib_recv_wr *wr,
 		      const struct ib_recv_wr **bad_wr)
 {
@@ -79,6 +114,8 @@ int mana_ib_post_recv(struct ib_qp *ibqp, const struct ib_recv_wr *wr,
 	case IB_QPT_UD:
 	case IB_QPT_GSI:
 		return mana_ib_post_recv_ud(qp, wr, bad_wr);
+	case IB_QPT_RC:
+		return mana_ib_post_recv_rc(qp, wr, bad_wr);
 	default:
 		/* Unsupported QP type */
 		*bad_wr = wr;
-- 
2.43.0