From: Huy Nguyen <huyn@mellanox.com>
Date: Tue, 30 May 2017 09:42:54 +0300
Subject: IB/mlx5: Add raw ethernet local loopback support
Patch-mainline: v4.14-rc1
Git-commit: c85023e153e3824661d07307138fdeff41f6d86a
References: bsc#1046305 FATE#322943

Currently, unicast/multicast loopback raw ethernet
(non-RDMA) packets are sent back to the vport.
A unicast loopback packet is the packet with destination
MAC address the same as the source MAC address.
For multicast, the destination MAC address is in the
vport's multicast filter list.

Moreover, the local loopback is not needed if
there is one or none user space context.

After this patch, the raw ethernet unicast and multicast
local loopback are disabled by default. When there is more
than one user space context, the local loopback is enabled.

Note that when local loopback is disabled, raw ethernet
packets are not looped back to the vport and are forwarded
to the next routing level (eswitch, or multihost switch,
or out to the wire depending on the configuration).

Signed-off-by: Huy Nguyen <huyn@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/infiniband/hw/mlx5/main.c              |   51 +++++++++++++++++++++++--
 drivers/infiniband/hw/mlx5/mlx5_ib.h           |   10 +++-
 drivers/net/ethernet/mellanox/mlx5/core/main.c |   19 +++++++++
 3 files changed, 73 insertions(+), 7 deletions(-)

--- a/drivers/infiniband/hw/mlx5/main.c
+++ b/drivers/infiniband/hw/mlx5/main.c
@@ -58,6 +58,7 @@
 #include <linux/mlx5/vport.h>
 #include "mlx5_ib.h"
 #include "cmd.h"
+#include <linux/mlx5/vport.h>
 
 #define DRIVER_NAME "mlx5_ib"
 #define DRIVER_VERSION "5.0-0"
@@ -1193,6 +1194,45 @@ static int deallocate_uars(struct mlx5_i
 	return 0;
 }
 
+static int mlx5_ib_alloc_transport_domain(struct mlx5_ib_dev *dev, u32 *tdn)
+{
+	int err;
+
+	err = mlx5_core_alloc_transport_domain(dev->mdev, tdn);
+	if (err)
+		return err;
+
+	if ((MLX5_CAP_GEN(dev->mdev, port_type) != MLX5_CAP_PORT_TYPE_ETH) ||
+	    !MLX5_CAP_GEN(dev->mdev, disable_local_lb))
+		return err;
+
+	mutex_lock(&dev->lb_mutex);
+	dev->user_td++;
+
+	if (dev->user_td == 2)
+		err = mlx5_nic_vport_update_local_lb(dev->mdev, true);
+
+	mutex_unlock(&dev->lb_mutex);
+	return err;
+}
+
+static void mlx5_ib_dealloc_transport_domain(struct mlx5_ib_dev *dev, u32 tdn)
+{
+	mlx5_core_dealloc_transport_domain(dev->mdev, tdn);
+
+	if ((MLX5_CAP_GEN(dev->mdev, port_type) != MLX5_CAP_PORT_TYPE_ETH) ||
+	    !MLX5_CAP_GEN(dev->mdev, disable_local_lb))
+		return;
+
+	mutex_lock(&dev->lb_mutex);
+	dev->user_td--;
+
+	if (dev->user_td < 2)
+		mlx5_nic_vport_update_local_lb(dev->mdev, false);
+
+	mutex_unlock(&dev->lb_mutex);
+}
+
 static struct ib_ucontext *mlx5_ib_alloc_ucontext(struct ib_device *ibdev,
 						  struct ib_udata *udata)
 {
@@ -1301,8 +1341,7 @@ static struct ib_ucontext *mlx5_ib_alloc
 	mutex_init(&context->upd_xlt_page_mutex);
 
 	if (MLX5_CAP_GEN(dev->mdev, log_max_transport_domain)) {
-		err = mlx5_core_alloc_transport_domain(dev->mdev,
-						       &context->tdn);
+		err = mlx5_ib_alloc_transport_domain(dev, &context->tdn);
 		if (err)
 			goto out_page;
 	}
@@ -1368,7 +1407,7 @@ static struct ib_ucontext *mlx5_ib_alloc
 
 out_td:
 	if (MLX5_CAP_GEN(dev->mdev, log_max_transport_domain))
-		mlx5_core_dealloc_transport_domain(dev->mdev, context->tdn);
+		mlx5_ib_dealloc_transport_domain(dev, context->tdn);
 
 out_page:
 	free_page(context->upd_xlt_page);
@@ -1396,7 +1435,7 @@ static int mlx5_ib_dealloc_ucontext(stru
 
 	bfregi = &context->bfregi;
 	if (MLX5_CAP_GEN(dev->mdev, log_max_transport_domain))
-		mlx5_core_dealloc_transport_domain(dev->mdev, context->tdn);
+		mlx5_ib_dealloc_transport_domain(dev, context->tdn);
 
 	free_page(context->upd_xlt_page);
 	deallocate_uars(dev, context);
@@ -3803,6 +3842,10 @@ static void *mlx5_ib_add(struct mlx5_cor
 			goto err_umrc;
 	}
 
+	if ((MLX5_CAP_GEN(mdev, port_type) == MLX5_CAP_PORT_TYPE_ETH) &&
+	    MLX5_CAP_GEN(mdev, disable_local_lb))
+		mutex_init(&dev->lb_mutex);
+
 	dev->ib_active = true;
 
 	return dev;
--- a/drivers/infiniband/hw/mlx5/mlx5_ib.h
+++ b/drivers/infiniband/hw/mlx5/mlx5_ib.h
@@ -652,9 +652,13 @@ struct mlx5_ib_dev {
 	struct list_head	qp_list;
 	/* Array with num_ports elements */
 	struct mlx5_ib_port	*port;
-	struct mlx5_sq_bfreg     bfreg;
-	struct mlx5_sq_bfreg     fp_bfreg;
-	u8				umr_fence;
+	struct mlx5_sq_bfreg	bfreg;
+	struct mlx5_sq_bfreg	fp_bfreg;
+
+	/* protect the user_td */
+	struct mutex		lb_mutex;
+	u32			user_td;
+	u8			umr_fence;
 };
 
 static inline struct mlx5_ib_cq *to_mibcq(struct mlx5_core_cq *mcq)
--- a/drivers/net/ethernet/mellanox/mlx5/core/main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/main.c
@@ -47,6 +47,7 @@
 #include <linux/debugfs.h>
 #include <linux/kmod.h>
 #include <linux/mlx5/mlx5_ifc.h>
+#include <linux/mlx5/vport.h>
 #ifdef CONFIG_RFS_ACCEL
 #include <linux/cpu_rmap.h>
 #endif
@@ -579,6 +580,18 @@ static int set_hca_ctrl(struct mlx5_core
 	return err;
 }
 
+static int mlx5_core_set_hca_defaults(struct mlx5_core_dev *dev)
+{
+	int ret = 0;
+
+	/* Disable local_lb by default */
+	if ((MLX5_CAP_GEN(dev, port_type) == MLX5_CAP_PORT_TYPE_ETH) &&
+	    MLX5_CAP_GEN(dev, disable_local_lb))
+		ret = mlx5_nic_vport_update_local_lb(dev, false);
+
+	return ret;
+}
+
 int mlx5_core_enable_hca(struct mlx5_core_dev *dev, u16 func_id)
 {
 	u32 out[MLX5_ST_SZ_DW(enable_hca_out)] = {0};
@@ -1155,6 +1168,12 @@ static int mlx5_load_one(struct mlx5_cor
 		goto err_fs;
 	}
 
+	err = mlx5_core_set_hca_defaults(dev);
+	if (err) {
+		dev_err(&pdev->dev, "Failed to set hca defaults\n");
+		goto err_fs;
+	}
+
 #ifdef CONFIG_MLX5_CORE_EN
 	mlx5_eswitch_attach(dev->priv.eswitch);
 #endif