net/mlx5: Geneve, Manage Geneve TLV options

Use Geneve TLV Options object to manage the flex parser matching
on the 32-bit options data.

When the first flow with a certain class/type values is requested to
be offloaded, create a FW object with FW command (Geneve TLV Options
general object) and start counting the number of flows using this object.

During this time, any request with a different class/type values will
fail to be offloaded.
Once the refcount reaches 0, destroy the TLV options general object,
and can now offload a flow with any class/type parameters.

Geneve TLV Options object is added to core device.
It is currently used to manage Geneve TLV options general
object allocation in FW and its reference counting only.
In the future it will also be used for managing geneve ports
by registering callbacks for ndo_udp_tunnel_add/del.

Reviewed-by: Oz Shlomo <ozsh@mellanox.com>
Signed-off-by: Yevgeny Kliteynik <kliteyn@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

2 files changed, 190 insertions, 0 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/lib/geneve.c b/drivers/net/ethernet/mellanox/mlx5/core/lib/geneve.c
new file mode 100644
index 000000000000..23361a9ae4fa
--- /dev/null
+++ b/drivers/net/ethernet/mellanox/mlx5/core/lib/geneve.c
@@ -0,0 +1,157 @@
+// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
+/* Copyright (c) 2019 Mellanox Technologies. */
+
+#include <linux/kernel.h>
+#include "mlx5_core.h"
+#include "geneve.h"
+
+struct mlx5_geneve {
+	struct mlx5_core_dev *mdev;
+	__be16 opt_class;
+	u8 opt_type;
+	u32 obj_id;
+	struct mutex sync_lock; /* protect GENEVE obj operations */
+	u32 refcount;
+};
+
+static int mlx5_geneve_tlv_option_create(struct mlx5_core_dev *mdev,
+					 __be16 class,
+					 u8 type,
+					 u8 len)
+{
+	u32 in[MLX5_ST_SZ_DW(create_geneve_tlv_option_in)] = {};
+	u32 out[MLX5_ST_SZ_DW(general_obj_out_cmd_hdr)] = {};
+	u64 general_obj_types;
+	void *hdr, *opt;
+	u16 obj_id;
+	int err;
+
+	general_obj_types = MLX5_CAP_GEN_64(mdev, general_obj_types);
+	if (!(general_obj_types & MLX5_GENERAL_OBJ_TYPES_CAP_GENEVE_TLV_OPT))
+		return -EINVAL;
+
+	hdr = MLX5_ADDR_OF(create_geneve_tlv_option_in, in, hdr);
+	opt = MLX5_ADDR_OF(create_geneve_tlv_option_in, in, geneve_tlv_opt);
+
+	MLX5_SET(general_obj_in_cmd_hdr, hdr, opcode, MLX5_CMD_OP_CREATE_GENERAL_OBJECT);
+	MLX5_SET(general_obj_in_cmd_hdr, hdr, obj_type, MLX5_OBJ_TYPE_GENEVE_TLV_OPT);
+
+	MLX5_SET(geneve_tlv_option, opt, option_class, be16_to_cpu(class));
+	MLX5_SET(geneve_tlv_option, opt, option_type, type);
+	MLX5_SET(geneve_tlv_option, opt, option_data_length, len);
+
+	err = mlx5_cmd_exec(mdev, in, sizeof(in), out, sizeof(out));
+	if (err)
+		return err;
+
+	obj_id = MLX5_GET(general_obj_out_cmd_hdr, out, obj_id);
+	return obj_id;
+}
+
+static void mlx5_geneve_tlv_option_destroy(struct mlx5_core_dev *mdev, u16 obj_id)
+{
+	u32 out[MLX5_ST_SZ_DW(general_obj_out_cmd_hdr)] = {};
+	u32 in[MLX5_ST_SZ_DW(general_obj_in_cmd_hdr)] = {};
+
+	MLX5_SET(general_obj_in_cmd_hdr, in, opcode, MLX5_CMD_OP_DESTROY_GENERAL_OBJECT);
+	MLX5_SET(general_obj_in_cmd_hdr, in, obj_type, MLX5_OBJ_TYPE_GENEVE_TLV_OPT);
+	MLX5_SET(general_obj_in_cmd_hdr, in, obj_id, obj_id);
+
+	mlx5_cmd_exec(mdev, in, sizeof(in), out, sizeof(out));
+}
+
+int mlx5_geneve_tlv_option_add(struct mlx5_geneve *geneve, struct geneve_opt *opt)
+{
+	int res = 0;
+
+	if (IS_ERR_OR_NULL(geneve))
+		return -EOPNOTSUPP;
+
+	mutex_lock(&geneve->sync_lock);
+
+	if (geneve->refcount) {
+		if (geneve->opt_class == opt->opt_class &&
+		    geneve->opt_type == opt->type) {
+			/* We already have TLV options obj allocated */
+			geneve->refcount++;
+		} else {
+			/* TLV options obj allocated, but its params
+			 * do not match the new request.
+			 * We support only one such object.
+			 */
+			mlx5_core_warn(geneve->mdev,
+				       "Won't create Geneve TLV opt object with class:type:len = 0x%x:0x%x:%d (another class:type already exists)\n",
+				       be16_to_cpu(opt->opt_class),
+				       opt->type,
+				       opt->length);
+			res = -EOPNOTSUPP;
+			goto unlock;
+		}
+	} else {
+		/* We don't have any TLV options obj allocated */
+
+		res = mlx5_geneve_tlv_option_create(geneve->mdev,
+						    opt->opt_class,
+						    opt->type,
+						    opt->length);
+		if (res < 0) {
+			mlx5_core_warn(geneve->mdev,
+				       "Failed creating Geneve TLV opt object class:type:len = 0x%x:0x%x:%d (err=%d)\n",
+				       be16_to_cpu(opt->opt_class),
+				       opt->type, opt->length, res);
+			goto unlock;
+		}
+		geneve->opt_class = opt->opt_class;
+		geneve->opt_type = opt->type;
+		geneve->obj_id = res;
+		geneve->refcount++;
+	}
+
+unlock:
+	mutex_unlock(&geneve->sync_lock);
+	return res;
+}
+
+void mlx5_geneve_tlv_option_del(struct mlx5_geneve *geneve)
+{
+	if (IS_ERR_OR_NULL(geneve))
+		return;
+
+	mutex_lock(&geneve->sync_lock);
+	if (--geneve->refcount == 0) {
+		/* We've just removed the last user of Geneve option.
+		 * Now delete the object in FW.
+		 */
+		mlx5_geneve_tlv_option_destroy(geneve->mdev, geneve->obj_id);
+
+		geneve->opt_class = 0;
+		geneve->opt_type = 0;
+		geneve->obj_id = 0;
+	}
+	mutex_unlock(&geneve->sync_lock);
+}
+
+struct mlx5_geneve *mlx5_geneve_create(struct mlx5_core_dev *mdev)
+{
+	struct mlx5_geneve *geneve =
+		kzalloc(sizeof(*geneve), GFP_KERNEL);
+
+	if (!geneve)
+		return ERR_PTR(-ENOMEM);
+	geneve->mdev = mdev;
+	mutex_init(&geneve->sync_lock);
+
+	return geneve;
+}
+
+void mlx5_geneve_destroy(struct mlx5_geneve *geneve)
+{
+	if (IS_ERR_OR_NULL(geneve))
+		return;
+
+	/* Lockless since we are unloading */
+	if (geneve->refcount)
+		mlx5_geneve_tlv_option_destroy(geneve->mdev, geneve->obj_id);
+
+	kfree(geneve);
+}
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/lib/geneve.h b/drivers/net/ethernet/mellanox/mlx5/core/lib/geneve.h
new file mode 100644
index 000000000000..adee0cbba19c
--- /dev/null
+++ b/drivers/net/ethernet/mellanox/mlx5/core/lib/geneve.h
@@ -0,0 +1,33 @@
+/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
+/* Copyright (c) 2019 Mellanox Technologies. */
+
+#ifndef __MLX5_GENEVE_H__
+#define __MLX5_GENEVE_H__
+
+#include <net/geneve.h>
+#include <linux/mlx5/driver.h>
+
+struct mlx5_geneve;
+
+#ifdef CONFIG_MLX5_ESWITCH
+
+struct mlx5_geneve *mlx5_geneve_create(struct mlx5_core_dev *mdev);
+void mlx5_geneve_destroy(struct mlx5_geneve *geneve);
+
+int mlx5_geneve_tlv_option_add(struct mlx5_geneve *geneve, struct geneve_opt *opt);
+void mlx5_geneve_tlv_option_del(struct mlx5_geneve *geneve);
+
+#else /* CONFIG_MLX5_ESWITCH */
+
+static inline struct mlx5_geneve
+*mlx5_geneve_create(struct mlx5_core_dev *mdev) { return NULL; }
+static inline void
+mlx5_geneve_destroy(struct mlx5_geneve *geneve) {}
+static inline int
+mlx5_geneve_tlv_option_add(struct mlx5_geneve *geneve, struct geneve_opt *opt) { return 0; }
+static inline void
+mlx5_geneve_tlv_option_del(struct mlx5_geneve *geneve) {}
+
+#endif /* CONFIG_MLX5_ESWITCH */
+
+#endif /* __MLX5_GENEVE_H__ */