net/mlx5: Eswitch, enable RoCE loopback traffic

When in switchdev mode, we would like to treat loopback RoCE
traffic (on eswitch manager) as RDMA and not as regular
Ethernet traffic
In order to enable it we add flow steering rule that forward RoCE
loopback traffic to the HW RoCE filter (by adding allow rule).
In addition we add RoCE address in GID index 0, which will be
set in the RoCE loopback packet.

Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Reviewed-by: Mark Bloch <markb@mellanox.com>
Acked-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

drivers/net/ethernet/mellanox/mlx5/core/Makefile

@@ -35,7 +35,7 @@ mlx5_core-$(CONFIG_MLX5_ESWITCH)     += en_rep.o en_tc.o en/tc_tun.o lib/port_tu
 #
 # Core extra
 #
-mlx5_core-$(CONFIG_MLX5_ESWITCH)   += eswitch.o eswitch_offloads.o ecpf.o
+mlx5_core-$(CONFIG_MLX5_ESWITCH)   += eswitch.o eswitch_offloads.o ecpf.o rdma.o
 mlx5_core-$(CONFIG_MLX5_MPFS)      += lib/mpfs.o
 mlx5_core-$(CONFIG_VXLAN)          += lib/vxlan.o
 mlx5_core-$(CONFIG_PTP_1588_CLOCK) += lib/clock.o

drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c

@@ -37,6 +37,7 @@
 #include <linux/mlx5/fs.h>
 #include "mlx5_core.h"
 #include "eswitch.h"
+#include "rdma.h"
 #include "en.h"
 #include "fs_core.h"
 #include "lib/devcom.h"
@@ -1713,6 +1714,8 @@ int esw_offloads_init(struct mlx5_eswitch *esw, int vf_nvports,
 		esw->host_info.num_vfs = vf_nvports;
 	}
 
+	mlx5_rdma_enable_roce(esw->dev);
+
 	return 0;
 
 err_reps:
@@ -1751,6 +1754,7 @@ void esw_offloads_cleanup(struct mlx5_eswitch *esw)
 		num_vfs = esw->dev->priv.sriov.num_vfs;
 	}
 
+	mlx5_rdma_disable_roce(esw->dev);
 	esw_offloads_devcom_cleanup(esw);
 	esw_offloads_unload_all_reps(esw, num_vfs);
 	esw_offloads_steering_cleanup(esw);

drivers/net/ethernet/mellanox/mlx5/core/rdma.c

@@ -0,0 +1,182 @@
+// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
+/* Copyright (c) 2019 Mellanox Technologies */
+
+#include <linux/mlx5/vport.h>
+#include <rdma/ib_verbs.h>
+#include <net/addrconf.h>
+
+#include "lib/mlx5.h"
+#include "eswitch.h"
+#include "fs_core.h"
+#include "rdma.h"
+
+static void mlx5_rdma_disable_roce_steering(struct mlx5_core_dev *dev)
+{
+	struct mlx5_core_roce *roce = &dev->priv.roce;
+
+	if (!roce->ft)
+		return;
+
+	mlx5_del_flow_rules(roce->allow_rule);
+	mlx5_destroy_flow_group(roce->fg);
+	mlx5_destroy_flow_table(roce->ft);
+}
+
+static int mlx5_rdma_enable_roce_steering(struct mlx5_core_dev *dev)
+{
+	int inlen = MLX5_ST_SZ_BYTES(create_flow_group_in);
+	struct mlx5_core_roce *roce = &dev->priv.roce;
+	struct mlx5_flow_handle *flow_rule = NULL;
+	struct mlx5_flow_table_attr ft_attr = {};
+	struct mlx5_flow_namespace *ns = NULL;
+	struct mlx5_flow_act flow_act = {};
+	struct mlx5_flow_spec *spec;
+	struct mlx5_flow_table *ft;
+	struct mlx5_flow_group *fg;
+	void *match_criteria;
+	u32 *flow_group_in;
+	void *misc;
+	int err;
+
+	if (!(MLX5_CAP_FLOWTABLE_RDMA_RX(dev, ft_support) &&
+	      MLX5_CAP_FLOWTABLE_RDMA_RX(dev, table_miss_action_domain)))
+		return -EOPNOTSUPP;
+
+	flow_group_in = kvzalloc(inlen, GFP_KERNEL);
+	if (!flow_group_in)
+		return -ENOMEM;
+	spec = kvzalloc(sizeof(*spec), GFP_KERNEL);
+	if (!spec) {
+		kvfree(flow_group_in);
+		return -ENOMEM;
+	}
+
+	ns = mlx5_get_flow_namespace(dev, MLX5_FLOW_NAMESPACE_RDMA_RX);
+	if (!ns) {
+		mlx5_core_err(dev, "Failed to get RDMA RX namespace");
+		err = -EOPNOTSUPP;
+		goto free;
+	}
+
+	ft_attr.max_fte = 1;
+	ft = mlx5_create_flow_table(ns, &ft_attr);
+	if (IS_ERR(ft)) {
+		mlx5_core_err(dev, "Failed to create RDMA RX flow table");
+		err = PTR_ERR(ft);
+		goto free;
+	}
+
+	MLX5_SET(create_flow_group_in, flow_group_in, match_criteria_enable,
+		 MLX5_MATCH_MISC_PARAMETERS);
+	match_criteria = MLX5_ADDR_OF(create_flow_group_in, flow_group_in,
+				      match_criteria);
+	MLX5_SET_TO_ONES(fte_match_param, match_criteria,
+			 misc_parameters.source_port);
+
+	fg = mlx5_create_flow_group(ft, flow_group_in);
+	if (IS_ERR(fg)) {
+		err = PTR_ERR(fg);
+		mlx5_core_err(dev, "Failed to create RDMA RX flow group err(%d)\n", err);
+		goto destroy_flow_table;
+	}
+
+	spec->match_criteria_enable = MLX5_MATCH_MISC_PARAMETERS;
+	misc = MLX5_ADDR_OF(fte_match_param, spec->match_value,
+			    misc_parameters);
+	MLX5_SET(fte_match_set_misc, misc, source_port,
+		 dev->priv.eswitch->manager_vport);
+	misc = MLX5_ADDR_OF(fte_match_param, spec->match_criteria,
+			    misc_parameters);
+	MLX5_SET_TO_ONES(fte_match_set_misc, misc, source_port);
+
+	flow_act.action = MLX5_FLOW_CONTEXT_ACTION_ALLOW;
+	flow_rule = mlx5_add_flow_rules(ft, spec, &flow_act, NULL, 0);
+	if (IS_ERR(flow_rule)) {
+		err = PTR_ERR(flow_rule);
+		mlx5_core_err(dev, "Failed to add RoCE allow rule, err=%d\n",
+			      err);
+		goto destroy_flow_group;
+	}
+
+	kvfree(spec);
+	kvfree(flow_group_in);
+	roce->ft = ft;
+	roce->fg = fg;
+	roce->allow_rule = flow_rule;
+
+	return 0;
+
+destroy_flow_table:
+	mlx5_destroy_flow_table(ft);
+destroy_flow_group:
+	mlx5_destroy_flow_group(fg);
+free:
+	kvfree(spec);
+	kvfree(flow_group_in);
+	return err;
+}
+
+static void mlx5_rdma_del_roce_addr(struct mlx5_core_dev *dev)
+{
+	mlx5_core_roce_gid_set(dev, 0, 0, 0,
+			       NULL, NULL, false, 0, 0);
+}
+
+static void mlx5_rdma_make_default_gid(struct mlx5_core_dev *dev, union ib_gid *gid)
+{
+	u8 hw_id[ETH_ALEN];
+
+	mlx5_query_nic_vport_mac_address(dev, 0, hw_id);
+	gid->global.subnet_prefix = cpu_to_be64(0xfe80000000000000LL);
+	addrconf_addr_eui48(&gid->raw[8], hw_id);
+}
+
+static int mlx5_rdma_add_roce_addr(struct mlx5_core_dev *dev)
+{
+	union ib_gid gid;
+	u8 mac[ETH_ALEN];
+
+	mlx5_rdma_make_default_gid(dev, &gid);
+	return mlx5_core_roce_gid_set(dev, 0,
+				      MLX5_ROCE_VERSION_1,
+				      0, gid.raw, mac,
+				      false, 0, 1);
+}
+
+void mlx5_rdma_disable_roce(struct mlx5_core_dev *dev)
+{
+	mlx5_rdma_disable_roce_steering(dev);
+	mlx5_rdma_del_roce_addr(dev);
+	mlx5_nic_vport_disable_roce(dev);
+}
+
+void mlx5_rdma_enable_roce(struct mlx5_core_dev *dev)
+{
+	int err;
+
+	err = mlx5_nic_vport_enable_roce(dev);
+	if (err) {
+		mlx5_core_err(dev, "Failed to enable RoCE: %d\n", err);
+		return;
+	}
+
+	err = mlx5_rdma_add_roce_addr(dev);
+	if (err) {
+		mlx5_core_err(dev, "Failed to add RoCE address: %d\n", err);
+		goto disable_roce;
+	}
+
+	err = mlx5_rdma_enable_roce_steering(dev);
+	if (err) {
+		mlx5_core_err(dev, "Failed to enable RoCE steering: %d\n", err);
+		goto del_roce_addr;
+	}
+
+	return;
+
+del_roce_addr:
+	mlx5_rdma_del_roce_addr(dev);
+disable_roce:
+	mlx5_nic_vport_disable_roce(dev);
+	return;
+}

drivers/net/ethernet/mellanox/mlx5/core/rdma.h

@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
+/* Copyright (c) 2019 Mellanox Technologies. */
+
+#ifndef __MLX5_RDMA_H__
+#define __MLX5_RDMA_H__
+
+#include "mlx5_core.h"
+
+#ifdef CONFIG_MLX5_ESWITCH
+
+void mlx5_rdma_enable_roce(struct mlx5_core_dev *dev);
+void mlx5_rdma_disable_roce(struct mlx5_core_dev *dev);
+
+#else /* CONFIG_MLX5_ESWITCH */
+
+static inline void mlx5_rdma_enable_roce(struct mlx5_core_dev *dev) {}
+static inline void mlx5_rdma_disable_roce(struct mlx5_core_dev *dev) {}
+
+#endif /* CONFIG_MLX5_ESWITCH */
+#endif /* __MLX5_RDMA_H__ */

include/linux/mlx5/driver.h

@@ -512,6 +512,12 @@ struct mlx5_rl_table {
 	struct mlx5_rl_entry   *rl_entry;
 };
 
+struct mlx5_core_roce {
+	struct mlx5_flow_table *ft;
+	struct mlx5_flow_group *fg;
+	struct mlx5_flow_handle *allow_rule;
+};
+
 struct mlx5_priv {
 	struct mlx5_eq_table	*eq_table;
 
@@ -565,6 +571,7 @@ struct mlx5_priv {
 	struct mlx5_lag		*lag;
 	struct mlx5_devcom	*devcom;
 	unsigned long		pci_dev_data;
+	struct mlx5_core_roce	roce;
 	struct mlx5_fc_stats		fc_stats;
 	struct mlx5_rl_table            rl_table;