IB/mlx4: Fix VF mac handling in RoCE

We had several problems here.  First, a race condition on QP1 mac
handling between mlx4_ib_update_qps and mlx4_ib_modify_qp, which is
fixed by taking the qp mutex in mlx4_ib_update_qps.

Also, qp->pri.smac_port was not updated in mlx4_ib_update_qps.

Last, in __mlx4_ib_modify_qp we did not properly handle the case where
the mac is zero, but port is non-zero.

Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

diff --git a/drivers/infiniband/hw/mlx4/main.c b/drivers/infiniband/hw/mlx4/main.c
index d57563b..c7586a1 100644 (file)
--- a/drivers/infiniband/hw/mlx4/main.c
+++ b/drivers/infiniband/hw/mlx4/main.c
@@ -1667,9 +1667,11 @@ static void mlx4_ib_update_qps(struct mlx4_ib_dev *ibdev,
        qp = ibdev->qp1_proxy[port - 1];
        if (qp) {
                int new_smac_index;
-               u64 old_smac = qp->pri.smac;
+               u64 old_smac;
                struct mlx4_update_qp_params update_params;
 
+               mutex_lock(&qp->mutex);
+               old_smac = qp->pri.smac;
                if (new_smac == old_smac)
                        goto unlock;
 
@@ -1684,17 +1686,20 @@ static void mlx4_ib_update_qps(struct mlx4_ib_dev *ibdev,
                        release_mac = new_smac;
                        goto unlock;
                }
-
+               /* if old port was zero, no mac was yet registered for this QP */
+               if (qp->pri.smac_port)
+                       release_mac = old_smac;
                qp->pri.smac = new_smac;
+               qp->pri.smac_port = port;
                qp->pri.smac_index = new_smac_index;
-
-               release_mac = old_smac;
        }
 
 unlock:
-       mutex_unlock(&ibdev->qp1_proxy_lock[port - 1]);
        if (release_mac != MLX4_IB_INVALID_MAC)
                mlx4_unregister_mac(ibdev->dev, port, release_mac);
+       if (qp)
+               mutex_unlock(&qp->mutex);
+       mutex_unlock(&ibdev->qp1_proxy_lock[port - 1]);
 }
 
 static void mlx4_ib_get_dev_addr(struct net_device *dev,

diff --git a/drivers/infiniband/hw/mlx4/qp.c b/drivers/infiniband/hw/mlx4/qp.c
index 393423c..577b477 100644 (file)
--- a/drivers/infiniband/hw/mlx4/qp.c
+++ b/drivers/infiniband/hw/mlx4/qp.c
@@ -964,9 +964,10 @@ static void destroy_qp_common(struct mlx4_ib_dev *dev, struct mlx4_ib_qp *qp,
                                   MLX4_QP_STATE_RST, NULL, 0, 0, &qp->mqp))
                        pr_warn("modify QP %06x to RESET failed.\n",
                               qp->mqp.qpn);
-               if (qp->pri.smac) {
+               if (qp->pri.smac || (!qp->pri.smac && qp->pri.smac_port)) {
                        mlx4_unregister_mac(dev->dev, qp->pri.smac_port, qp->pri.smac);
                        qp->pri.smac = 0;
+                       qp->pri.smac_port = 0;
                }
                if (qp->alt.smac) {
                        mlx4_unregister_mac(dev->dev, qp->alt.smac_port, qp->alt.smac);
@@ -1325,7 +1326,8 @@ static int _mlx4_set_path(struct mlx4_ib_dev *dev, const struct ib_ah_attr *ah,
                 * If one was already assigned, but the new mac differs,
                 * unregister the old one and register the new one.
                */
-               if (!smac_info->smac || smac_info->smac != smac) {
+               if ((!smac_info->smac && !smac_info->smac_port) ||
+                   smac_info->smac != smac) {
                        /* register candidate now, unreg if needed, after success */
                        smac_index = mlx4_register_mac(dev->dev, port, smac);
                        if (smac_index >= 0) {
@@ -1396,7 +1398,7 @@ static int handle_eth_ud_smac_index(struct mlx4_ib_dev *dev, struct mlx4_ib_qp *
        u64_mac = atomic64_read(&dev->iboe.mac[qp->port - 1]);
 
        context->pri_path.sched_queue = MLX4_IB_DEFAULT_SCHED_QUEUE | ((qp->port - 1) << 6);
-       if (!qp->pri.smac) {
+       if (!qp->pri.smac && !qp->pri.smac_port) {
                smac_index = mlx4_register_mac(dev->dev, qp->port, u64_mac);
                if (smac_index >= 0) {
                        qp->pri.candidate_smac_index = smac_index;
@@ -1778,9 +1780,10 @@ static int __mlx4_ib_modify_qp(struct ib_qp *ibqp,
                        if (qp->flags & MLX4_IB_QP_NETIF)
                                mlx4_ib_steer_qp_reg(dev, qp, 0);
                }
-               if (qp->pri.smac) {
+               if (qp->pri.smac || (!qp->pri.smac && qp->pri.smac_port)) {
                        mlx4_unregister_mac(dev->dev, qp->pri.smac_port, qp->pri.smac);
                        qp->pri.smac = 0;
+                       qp->pri.smac_port = 0;
                }
                if (qp->alt.smac) {
                        mlx4_unregister_mac(dev->dev, qp->alt.smac_port, qp->alt.smac);
@@ -1804,11 +1807,12 @@ out:
        if (err && steer_qp)
                mlx4_ib_steer_qp_reg(dev, qp, 0);
        kfree(context);
-       if (qp->pri.candidate_smac) {
+       if (qp->pri.candidate_smac ||
+           (!qp->pri.candidate_smac && qp->pri.candidate_smac_port)) {
                if (err) {
                        mlx4_unregister_mac(dev->dev, qp->pri.candidate_smac_port, qp->pri.candidate_smac);
                } else {
-                       if (qp->pri.smac)
+                       if (qp->pri.smac || (!qp->pri.smac && qp->pri.smac_port))
                                mlx4_unregister_mac(dev->dev, qp->pri.smac_port, qp->pri.smac);
                        qp->pri.smac = qp->pri.candidate_smac;
                        qp->pri.smac_index = qp->pri.candidate_smac_index;