IB/mlx4: Add support for steerable IB UD QPs

This patch adds support for steerable (NETIF) QP creation.  When we
create the device, we allocate a range of steerable QPs.

Afterward when a QP is created with the NETIF flag, it's allocated
from this range.  Allocation is managed by bitmap allocator.

Internal steering rules for those QPs is automatically generated on
their creation.

Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

1 files changed, 105 insertions, 1 deletions

diff --git a/drivers/infiniband/hw/mlx4/main.c b/drivers/infiniband/hw/mlx4/main.c
index 6b7f227ca9e4..ea5844e89b2a 100644
--- a/drivers/infiniband/hw/mlx4/main.c
+++ b/drivers/infiniband/hw/mlx4/main.c
@@ -1850,8 +1850,35 @@ static void *mlx4_ib_add(struct mlx4_dev *dev)
 	spin_lock_init(&ibdev->sm_lock);
 	mutex_init(&ibdev->cap_mask_mutex);
 
+	if (ibdev->steering_support == MLX4_STEERING_MODE_DEVICE_MANAGED) {
+		ibdev->steer_qpn_count = MLX4_IB_UC_MAX_NUM_QPS;
+		err = mlx4_qp_reserve_range(dev, ibdev->steer_qpn_count,
+					    MLX4_IB_UC_STEER_QPN_ALIGN,
+					    &ibdev->steer_qpn_base);
+		if (err)
+			goto err_counter;
+
+		ibdev->ib_uc_qpns_bitmap =
+			kmalloc(BITS_TO_LONGS(ibdev->steer_qpn_count) *
+				sizeof(long),
+				GFP_KERNEL);
+		if (!ibdev->ib_uc_qpns_bitmap) {
+			dev_err(&dev->pdev->dev, "bit map alloc failed\n");
+			goto err_steer_qp_release;
+		}
+
+		bitmap_zero(ibdev->ib_uc_qpns_bitmap, ibdev->steer_qpn_count);
+
+		err = mlx4_FLOW_STEERING_IB_UC_QP_RANGE(
+				dev, ibdev->steer_qpn_base,
+				ibdev->steer_qpn_base +
+				ibdev->steer_qpn_count - 1);
+		if (err)
+			goto err_steer_free_bitmap;
+	}
+
 	if (ib_register_device(&ibdev->ib_dev, NULL))
-		goto err_counter;
+		goto err_steer_free_bitmap;
 
 	if (mlx4_ib_mad_init(ibdev))
 		goto err_reg;
@@ -1902,6 +1929,13 @@ err_mad:
 err_reg:
 	ib_unregister_device(&ibdev->ib_dev);
 
+err_steer_free_bitmap:
+	kfree(ibdev->ib_uc_qpns_bitmap);
+
+err_steer_qp_release:
+	if (ibdev->steering_support == MLX4_STEERING_MODE_DEVICE_MANAGED)
+		mlx4_qp_release_range(dev, ibdev->steer_qpn_base,
+				      ibdev->steer_qpn_count);
 err_counter:
 	for (; i; --i)
 		if (ibdev->counters[i - 1] != -1)
@@ -1922,6 +1956,69 @@ err_dealloc:
 	return NULL;
 }
 
+int mlx4_ib_steer_qp_alloc(struct mlx4_ib_dev *dev, int count, int *qpn)
+{
+	int offset;
+
+	WARN_ON(!dev->ib_uc_qpns_bitmap);
+
+	offset = bitmap_find_free_region(dev->ib_uc_qpns_bitmap,
+					 dev->steer_qpn_count,
+					 get_count_order(count));
+	if (offset < 0)
+		return offset;
+
+	*qpn = dev->steer_qpn_base + offset;
+	return 0;
+}
+
+void mlx4_ib_steer_qp_free(struct mlx4_ib_dev *dev, u32 qpn, int count)
+{
+	if (!qpn ||
+	    dev->steering_support != MLX4_STEERING_MODE_DEVICE_MANAGED)
+		return;
+
+	BUG_ON(qpn < dev->steer_qpn_base);
+
+	bitmap_release_region(dev->ib_uc_qpns_bitmap,
+			      qpn - dev->steer_qpn_base,
+			      get_count_order(count));
+}
+
+int mlx4_ib_steer_qp_reg(struct mlx4_ib_dev *mdev, struct mlx4_ib_qp *mqp,
+			 int is_attach)
+{
+	int err;
+	size_t flow_size;
+	struct ib_flow_attr *flow = NULL;
+	struct ib_flow_spec_ib *ib_spec;
+
+	if (is_attach) {
+		flow_size = sizeof(struct ib_flow_attr) +
+			    sizeof(struct ib_flow_spec_ib);
+		flow = kzalloc(flow_size, GFP_KERNEL);
+		if (!flow)
+			return -ENOMEM;
+		flow->port = mqp->port;
+		flow->num_of_specs = 1;
+		flow->size = flow_size;
+		ib_spec = (struct ib_flow_spec_ib *)(flow + 1);
+		ib_spec->type = IB_FLOW_SPEC_IB;
+		ib_spec->size = sizeof(struct ib_flow_spec_ib);
+		/* Add an empty rule for IB L2 */
+		memset(&ib_spec->mask, 0, sizeof(ib_spec->mask));
+
+		err = __mlx4_ib_create_flow(&mqp->ibqp, flow,
+					    IB_FLOW_DOMAIN_NIC,
+					    MLX4_FS_REGULAR,
+					    &mqp->reg_id);
+	} else {
+		err = __mlx4_ib_destroy_flow(mdev->dev, mqp->reg_id);
+	}
+	kfree(flow);
+	return err;
+}
+
 static void mlx4_ib_remove(struct mlx4_dev *dev, void *ibdev_ptr)
 {
 	struct mlx4_ib_dev *ibdev = ibdev_ptr;
@@ -1935,6 +2032,13 @@ static void mlx4_ib_remove(struct mlx4_dev *dev, void *ibdev_ptr)
 			pr_warn("failure unregistering notifier\n");
 		ibdev->iboe.nb.notifier_call = NULL;
 	}
+
+	if (ibdev->steering_support == MLX4_STEERING_MODE_DEVICE_MANAGED) {
+		mlx4_qp_release_range(dev, ibdev->steer_qpn_base,
+				      ibdev->steer_qpn_count);
+		kfree(ibdev->ib_uc_qpns_bitmap);
+	}
+
 	iounmap(ibdev->uar_map);
 	for (p = 0; p < ibdev->num_ports; ++p)
 		if (ibdev->counters[p] != -1)