net/mlx5e: Receive flow steering framework for accelerated TCP flows

The framework allows creating flow tables to steer incoming traffic of
TCP sockets to the acceleration TIRs.
This is used in downstream patches for TLS, and will be used in the
future for other offloads.

Signed-off-by: Boris Pismenny <borisp@mellanox.com>
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

2 files changed, 298 insertions, 0 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/fs_tcp.c b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/fs_tcp.c
new file mode 100644
index 000000000000..a0e9082e15b0
--- /dev/null
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/fs_tcp.c
@@ -0,0 +1,280 @@
+// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
+/* Copyright (c) 2020, Mellanox Technologies inc. All rights reserved. */
+
+#include <linux/netdevice.h>
+#include "en_accel/fs_tcp.h"
+#include "fs_core.h"
+
+enum accel_fs_tcp_type {
+	ACCEL_FS_IPV4_TCP,
+	ACCEL_FS_IPV6_TCP,
+	ACCEL_FS_TCP_NUM_TYPES,
+};
+
+struct mlx5e_accel_fs_tcp {
+	struct mlx5e_flow_table tables[ACCEL_FS_TCP_NUM_TYPES];
+	struct mlx5_flow_handle *default_rules[ACCEL_FS_TCP_NUM_TYPES];
+};
+
+static enum mlx5e_traffic_types fs_accel2tt(enum accel_fs_tcp_type i)
+{
+	switch (i) {
+	case ACCEL_FS_IPV4_TCP:
+		return MLX5E_TT_IPV4_TCP;
+	default: /* ACCEL_FS_IPV6_TCP */
+		return MLX5E_TT_IPV6_TCP;
+	}
+}
+
+static int accel_fs_tcp_add_default_rule(struct mlx5e_priv *priv,
+					 enum accel_fs_tcp_type type)
+{
+	struct mlx5e_flow_table *accel_fs_t;
+	struct mlx5_flow_destination dest;
+	struct mlx5e_accel_fs_tcp *fs_tcp;
+	MLX5_DECLARE_FLOW_ACT(flow_act);
+	struct mlx5_flow_handle *rule;
+	int err = 0;
+
+	fs_tcp = priv->fs.accel_tcp;
+	accel_fs_t = &fs_tcp->tables[type];
+
+	dest = mlx5e_ttc_get_default_dest(priv, fs_accel2tt(type));
+	rule = mlx5_add_flow_rules(accel_fs_t->t, NULL, &flow_act, &dest, 1);
+	if (IS_ERR(rule)) {
+		err = PTR_ERR(rule);
+		netdev_err(priv->netdev,
+			   "%s: add default rule failed, accel_fs type=%d, err %d\n",
+			   __func__, type, err);
+		return err;
+	}
+
+	fs_tcp->default_rules[type] = rule;
+	return 0;
+}
+
+#define MLX5E_ACCEL_FS_TCP_NUM_GROUPS	(2)
+#define MLX5E_ACCEL_FS_TCP_GROUP1_SIZE	(BIT(16) - 1)
+#define MLX5E_ACCEL_FS_TCP_GROUP2_SIZE	(BIT(0))
+#define MLX5E_ACCEL_FS_TCP_TABLE_SIZE	(MLX5E_ACCEL_FS_TCP_GROUP1_SIZE +\
+					 MLX5E_ACCEL_FS_TCP_GROUP2_SIZE)
+static int accel_fs_tcp_create_groups(struct mlx5e_flow_table *ft,
+				      enum accel_fs_tcp_type type)
+{
+	int inlen = MLX5_ST_SZ_BYTES(create_flow_group_in);
+	void *outer_headers_c;
+	int ix = 0;
+	u32 *in;
+	int err;
+	u8 *mc;
+
+	ft->g = kcalloc(MLX5E_ACCEL_FS_TCP_NUM_GROUPS, sizeof(*ft->g), GFP_KERNEL);
+	in = kvzalloc(inlen, GFP_KERNEL);
+	if  (!in || !ft->g) {
+		kvfree(ft->g);
+		kvfree(in);
+		return -ENOMEM;
+	}
+
+	mc = MLX5_ADDR_OF(create_flow_group_in, in, match_criteria);
+	outer_headers_c = MLX5_ADDR_OF(fte_match_param, mc, outer_headers);
+	MLX5_SET_TO_ONES(fte_match_set_lyr_2_4, outer_headers_c, ip_protocol);
+	MLX5_SET_TO_ONES(fte_match_set_lyr_2_4, outer_headers_c, ip_version);
+
+	switch (type) {
+	case ACCEL_FS_IPV4_TCP:
+	case ACCEL_FS_IPV6_TCP:
+		MLX5_SET_TO_ONES(fte_match_set_lyr_2_4, outer_headers_c, tcp_dport);
+		MLX5_SET_TO_ONES(fte_match_set_lyr_2_4, outer_headers_c, tcp_sport);
+		break;
+	default:
+		err = -EINVAL;
+		goto out;
+	}
+
+	switch (type) {
+	case ACCEL_FS_IPV4_TCP:
+		MLX5_SET_TO_ONES(fte_match_set_lyr_2_4, outer_headers_c,
+				 src_ipv4_src_ipv6.ipv4_layout.ipv4);
+		MLX5_SET_TO_ONES(fte_match_set_lyr_2_4, outer_headers_c,
+				 dst_ipv4_dst_ipv6.ipv4_layout.ipv4);
+		break;
+	case ACCEL_FS_IPV6_TCP:
+		memset(MLX5_ADDR_OF(fte_match_set_lyr_2_4, outer_headers_c,
+				    src_ipv4_src_ipv6.ipv6_layout.ipv6),
+		       0xff, 16);
+		memset(MLX5_ADDR_OF(fte_match_set_lyr_2_4, outer_headers_c,
+				    dst_ipv4_dst_ipv6.ipv6_layout.ipv6),
+		       0xff, 16);
+		break;
+	default:
+		err = -EINVAL;
+		goto out;
+	}
+
+	MLX5_SET_CFG(in, match_criteria_enable, MLX5_MATCH_OUTER_HEADERS);
+	MLX5_SET_CFG(in, start_flow_index, ix);
+	ix += MLX5E_ACCEL_FS_TCP_GROUP1_SIZE;
+	MLX5_SET_CFG(in, end_flow_index, ix - 1);
+	ft->g[ft->num_groups] = mlx5_create_flow_group(ft->t, in);
+	if (IS_ERR(ft->g[ft->num_groups]))
+		goto err;
+	ft->num_groups++;
+
+	/* Default Flow Group */
+	memset(in, 0, inlen);
+	MLX5_SET_CFG(in, start_flow_index, ix);
+	ix += MLX5E_ACCEL_FS_TCP_GROUP2_SIZE;
+	MLX5_SET_CFG(in, end_flow_index, ix - 1);
+	ft->g[ft->num_groups] = mlx5_create_flow_group(ft->t, in);
+	if (IS_ERR(ft->g[ft->num_groups]))
+		goto err;
+	ft->num_groups++;
+
+	kvfree(in);
+	return 0;
+
+err:
+	err = PTR_ERR(ft->g[ft->num_groups]);
+	ft->g[ft->num_groups] = NULL;
+out:
+	kvfree(in);
+
+	return err;
+}
+
+static int accel_fs_tcp_create_table(struct mlx5e_priv *priv, enum accel_fs_tcp_type type)
+{
+	struct mlx5e_flow_table *ft = &priv->fs.accel_tcp->tables[type];
+	struct mlx5_flow_table_attr ft_attr = {};
+	int err;
+
+	ft->num_groups = 0;
+
+	ft_attr.max_fte = MLX5E_ACCEL_FS_TCP_TABLE_SIZE;
+	ft_attr.level = MLX5E_ACCEL_FS_TCP_FT_LEVEL;
+	ft_attr.prio = MLX5E_NIC_PRIO;
+
+	ft->t = mlx5_create_flow_table(priv->fs.ns, &ft_attr);
+	if (IS_ERR(ft->t)) {
+		err = PTR_ERR(ft->t);
+		ft->t = NULL;
+		return err;
+	}
+
+	netdev_dbg(priv->netdev, "Created fs accel table id %u level %u\n",
+		   ft->t->id, ft->t->level);
+
+	err = accel_fs_tcp_create_groups(ft, type);
+	if (err)
+		goto err;
+
+	err = accel_fs_tcp_add_default_rule(priv, type);
+	if (err)
+		goto err;
+
+	return 0;
+err:
+	mlx5e_destroy_flow_table(ft);
+	return err;
+}
+
+static int accel_fs_tcp_disable(struct mlx5e_priv *priv)
+{
+	int err, i;
+
+	for (i = 0; i < ACCEL_FS_TCP_NUM_TYPES; i++) {
+		/* Modify ttc rules destination to point back to the indir TIRs */
+		err = mlx5e_ttc_fwd_default_dest(priv, fs_accel2tt(i));
+		if (err) {
+			netdev_err(priv->netdev,
+				   "%s: modify ttc[%d] default destination failed, err(%d)\n",
+				   __func__, fs_accel2tt(i), err);
+			return err;
+		}
+	}
+
+	return 0;
+}
+
+static int accel_fs_tcp_enable(struct mlx5e_priv *priv)
+{
+	struct mlx5_flow_destination dest = {};
+	int err, i;
+
+	dest.type = MLX5_FLOW_DESTINATION_TYPE_FLOW_TABLE;
+	for (i = 0; i < ACCEL_FS_TCP_NUM_TYPES; i++) {
+		dest.ft = priv->fs.accel_tcp->tables[i].t;
+
+		/* Modify ttc rules destination to point on the accel_fs FTs */
+		err = mlx5e_ttc_fwd_dest(priv, fs_accel2tt(i), &dest);
+		if (err) {
+			netdev_err(priv->netdev,
+				   "%s: modify ttc[%d] destination to accel failed, err(%d)\n",
+				   __func__, fs_accel2tt(i), err);
+			return err;
+		}
+	}
+	return 0;
+}
+
+static void accel_fs_tcp_destroy_table(struct mlx5e_priv *priv, int i)
+{
+	struct mlx5e_accel_fs_tcp *fs_tcp;
+
+	fs_tcp = priv->fs.accel_tcp;
+	if (IS_ERR_OR_NULL(fs_tcp->tables[i].t))
+		return;
+
+	mlx5_del_flow_rules(fs_tcp->default_rules[i]);
+	mlx5e_destroy_flow_table(&fs_tcp->tables[i]);
+	fs_tcp->tables[i].t = NULL;
+}
+
+void mlx5e_accel_fs_tcp_destroy(struct mlx5e_priv *priv)
+{
+	int i;
+
+	if (!priv->fs.accel_tcp)
+		return;
+
+	accel_fs_tcp_disable(priv);
+
+	for (i = 0; i < ACCEL_FS_TCP_NUM_TYPES; i++)
+		accel_fs_tcp_destroy_table(priv, i);
+
+	kfree(priv->fs.accel_tcp);
+	priv->fs.accel_tcp = NULL;
+}
+
+int mlx5e_accel_fs_tcp_create(struct mlx5e_priv *priv)
+{
+	int i, err;
+
+	if (!MLX5_CAP_FLOWTABLE_NIC_RX(priv->mdev, ft_field_support.outer_ip_version))
+		return -EOPNOTSUPP;
+
+	priv->fs.accel_tcp = kzalloc(sizeof(*priv->fs.accel_tcp), GFP_KERNEL);
+	if (!priv->fs.accel_tcp)
+		return -ENOMEM;
+
+	for (i = 0; i < ACCEL_FS_TCP_NUM_TYPES; i++) {
+		err = accel_fs_tcp_create_table(priv, i);
+		if (err)
+			goto err_destroy_tables;
+	}
+
+	err = accel_fs_tcp_enable(priv);
+	if (err)
+		goto err_destroy_tables;
+
+	return 0;
+
+err_destroy_tables:
+	while (--i >= 0)
+		accel_fs_tcp_destroy_table(priv, i);
+
+	kfree(priv->fs.accel_tcp);
+	priv->fs.accel_tcp = NULL;
+	return err;
+}
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/fs_tcp.h b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/fs_tcp.h
new file mode 100644
index 000000000000..0df53473550a
--- /dev/null
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/fs_tcp.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
+/* Copyright (c) 2020, Mellanox Technologies inc. All rights reserved. */
+
+#ifndef __MLX5E_ACCEL_FS_TCP_H__
+#define __MLX5E_ACCEL_FS_TCP_H__
+
+#include "en.h"
+
+#ifdef CONFIG_MLX5_EN_TLS
+int mlx5e_accel_fs_tcp_create(struct mlx5e_priv *priv);
+void mlx5e_accel_fs_tcp_destroy(struct mlx5e_priv *priv);
+#else
+static inline int mlx5e_accel_fs_tcp_create(struct mlx5e_priv *priv) { return 0; }
+static inline void mlx5e_accel_fs_tcp_destroy(struct mlx5e_priv *priv) {}
+#endif
+
+#endif /* __MLX5E_ACCEL_FS_TCP_H__ */
+