From d1efc329df288e6249c8652723b9e120b71cccec Mon Sep 17 00:00:00 2001

From: Alaa Hleihel <ahleihel@redhat.com>

Date: Tue, 19 May 2020 07:48:51 -0400

Subject: [PATCH 229/312] [netdrv] net/mlx5: E-Switch, Mark miss packets with

 new chain id mapping

Message-id: <20200519074934.6303-21-ahleihel@redhat.com>

Patchwork-id: 310523

Patchwork-instance: patchwork

O-Subject: [RHEL8.3 BZ 1663246 20/63] net/mlx5: E-Switch, Mark miss packets with new chain id mapping

Bugzilla: 1790219 1790218 1663246

RH-Acked-by: Marcelo Leitner <mleitner@redhat.com>

RH-Acked-by: Jarod Wilson <jarod@redhat.com>

RH-Acked-by: John Linville <linville@redhat.com>

RH-Acked-by: Ivan Vecera <ivecera@redhat.com>

RH-Acked-by: Tony Camuso <tcamuso@redhat.com>

RH-Acked-by: Kamal Heib <kheib@redhat.com>

Bugzilla: http://bugzilla.redhat.com/1663246

Bugzilla: http://bugzilla.redhat.com/1790219

Bugzilla: http://bugzilla.redhat.com/1790218

Upstream: v5.7-rc1

commit 8f1e0b97cc708aa6a4d84b0431afc410feba00b6

Author: Paul Blakey <paulb@mellanox.com>

Date:   Sun Feb 16 12:01:28 2020 +0200

    net/mlx5: E-Switch, Mark miss packets with new chain id mapping

    Currently, if we miss in hardware after jumping to some chain,

    we continue in chain 0 in software. This is wrong, and with the new

    tc skb extension we can now restore the chain id on the skb, so

    tc can continue with in the correct chain.

    To restore the chain id in software after a miss in hardware, we create

    a register mapping from 32bit chain ids to 16bit of reg_c0 (that

    survives loopback), to 32bit chain ids. We then mark packets that

    miss on some chain with the current chain id mapping on their reg_c0

    field. Using this mapping, we will support up to 64K concurrent

    chains.

    This register survives loopback and gets to the CQE on flow_tag

    via the eswitch restore rules.

    In next commit, we will reverse the mapping we got on the CQE

    to a chain id and tell tc to continue in the sw chain where we

    left off via the tc skb extension.

    Signed-off-by: Paul Blakey <paulb@mellanox.com>

    Reviewed-by: Roi Dayan <roid@mellanox.com>

    Reviewed-by: Oz Shlomo <ozsh@mellanox.com>

    Reviewed-by: Mark Bloch <markb@mellanox.com>

    Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

Signed-off-by: Alaa Hleihel <ahleihel@redhat.com>

Signed-off-by: Frantisek Hrbata <fhrbata@redhat.com>

---

 drivers/net/ethernet/mellanox/mlx5/core/en_tc.c    |   8 ++

 drivers/net/ethernet/mellanox/mlx5/core/en_tc.h    |  12 ++

 .../mellanox/mlx5/core/eswitch_offloads_chains.c   | 130 ++++++++++++++++++++-

 .../mellanox/mlx5/core/eswitch_offloads_chains.h   |   4 +-

 4 files changed, 150 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c b/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c

index 9d6ac9a1461b..a9142bde2dc6 100644

--- a/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c

+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c

@@ -153,6 +153,14 @@ struct mlx5e_tc_flow_parse_attr {

 #define MLX5E_TC_TABLE_NUM_GROUPS 4

 #define MLX5E_TC_TABLE_MAX_GROUP_SIZE BIT(16)

+struct mlx5e_tc_attr_to_reg_mapping mlx5e_tc_attr_to_reg_mappings[] = {

+	[CHAIN_TO_REG] = {

+		.mfield = MLX5_ACTION_IN_FIELD_METADATA_REG_C_0,

+		.moffset = 0,

+		.mlen = 2,

+	},

+};

+

 struct mlx5e_hairpin {

 	struct mlx5_hairpin *pair;

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_tc.h b/drivers/net/ethernet/mellanox/mlx5/core/en_tc.h

index 262cdb7b69b1..e2dbbae6d4d7 100644

--- a/drivers/net/ethernet/mellanox/mlx5/core/en_tc.h

+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_tc.h

@@ -91,6 +91,18 @@ int mlx5e_tc_num_filters(struct mlx5e_priv *priv, unsigned long flags);

 void mlx5e_tc_reoffload_flows_work(struct work_struct *work);

+enum mlx5e_tc_attr_to_reg {

+	CHAIN_TO_REG,

+};

+

+struct mlx5e_tc_attr_to_reg_mapping {

+	int mfield; /* rewrite field */

+	int moffset; /* offset of mfield */

+	int mlen; /* bytes to rewrite/match */

+};

+

+extern struct mlx5e_tc_attr_to_reg_mapping mlx5e_tc_attr_to_reg_mappings[];

+

 bool mlx5e_is_valid_eswitch_fwd_dev(struct mlx5e_priv *priv,

 				    struct net_device *out_dev);

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads_chains.c b/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads_chains.c

index 6ffc4f041b6c..12ca184cd795 100644

--- a/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads_chains.c

+++ b/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads_chains.c

@@ -6,14 +6,17 @@

 #include <linux/mlx5/fs.h>

 #include "eswitch_offloads_chains.h"

+#include "en/mapping.h"

 #include "mlx5_core.h"

 #include "fs_core.h"

 #include "eswitch.h"

 #include "en.h"

+#include "en_tc.h"

 #define esw_chains_priv(esw) ((esw)->fdb_table.offloads.esw_chains_priv)

 #define esw_chains_lock(esw) (esw_chains_priv(esw)->lock)

 #define esw_chains_ht(esw) (esw_chains_priv(esw)->chains_ht)

+#define esw_chains_mapping(esw) (esw_chains_priv(esw)->chains_mapping)

 #define esw_prios_ht(esw) (esw_chains_priv(esw)->prios_ht)

 #define fdb_pool_left(esw) (esw_chains_priv(esw)->fdb_left)

 #define tc_slow_fdb(esw) ((esw)->fdb_table.offloads.slow_fdb)

@@ -42,6 +45,7 @@ struct mlx5_esw_chains_priv {

 	struct mutex lock;

 	struct mlx5_flow_table *tc_end_fdb;

+	struct mapping_ctx *chains_mapping;

 	int fdb_left[ARRAY_SIZE(ESW_POOLS)];

 };

@@ -52,9 +56,12 @@ struct fdb_chain {

 	u32 chain;

 	int ref;

+	int id;

 	struct mlx5_eswitch *esw;

 	struct list_head prios_list;

+	struct mlx5_flow_handle *restore_rule;

+	struct mlx5_modify_hdr *miss_modify_hdr;

 };

 struct fdb_prio_key {

@@ -258,6 +265,70 @@ mlx5_esw_chains_destroy_fdb_table(struct mlx5_eswitch *esw,

 	mlx5_destroy_flow_table(fdb);

 }

+static int

+create_fdb_chain_restore(struct fdb_chain *fdb_chain)

+{

+	char modact[MLX5_UN_SZ_BYTES(set_action_in_add_action_in_auto)];

+	struct mlx5_eswitch *esw = fdb_chain->esw;

+	struct mlx5_modify_hdr *mod_hdr;

+	u32 index;

+	int err;

+

+	if (fdb_chain->chain == mlx5_esw_chains_get_ft_chain(esw))

+		return 0;

+

+	err = mapping_add(esw_chains_mapping(esw), &fdb_chain->chain, &index);

+	if (err)

+		return err;

+	if (index == MLX5_FS_DEFAULT_FLOW_TAG) {

+		/* we got the special default flow tag id, so we won't know

+		 * if we actually marked the packet with the restore rule

+		 * we create.

+		 *

+		 * This case isn't possible with MLX5_FS_DEFAULT_FLOW_TAG = 0.

+		 */

+		err = mapping_add(esw_chains_mapping(esw),

+				  &fdb_chain->chain, &index);

+		mapping_remove(esw_chains_mapping(esw),

+			       MLX5_FS_DEFAULT_FLOW_TAG);

+		if (err)

+			return err;

+	}

+

+	fdb_chain->id = index;

+

+	MLX5_SET(set_action_in, modact, action_type, MLX5_ACTION_TYPE_SET);

+	MLX5_SET(set_action_in, modact, field,

+		 mlx5e_tc_attr_to_reg_mappings[CHAIN_TO_REG].mfield);

+	MLX5_SET(set_action_in, modact, offset,

+		 mlx5e_tc_attr_to_reg_mappings[CHAIN_TO_REG].moffset * 8);

+	MLX5_SET(set_action_in, modact, length,

+		 mlx5e_tc_attr_to_reg_mappings[CHAIN_TO_REG].mlen * 8);

+	MLX5_SET(set_action_in, modact, data, fdb_chain->id);

+	mod_hdr = mlx5_modify_header_alloc(esw->dev, MLX5_FLOW_NAMESPACE_FDB,

+					   1, modact);

+	if (IS_ERR(mod_hdr)) {

+		err = PTR_ERR(mod_hdr);

+		goto err_mod_hdr;

+	}

+	fdb_chain->miss_modify_hdr = mod_hdr;

+

+	fdb_chain->restore_rule = esw_add_restore_rule(esw, fdb_chain->id);

+	if (IS_ERR(fdb_chain->restore_rule)) {

+		err = PTR_ERR(fdb_chain->restore_rule);

+		goto err_rule;

+	}

+

+	return 0;

+

+err_rule:

+	mlx5_modify_header_dealloc(esw->dev, fdb_chain->miss_modify_hdr);

+err_mod_hdr:

+	/* Datapath can't find this mapping, so we can safely remove it */

+	mapping_remove(esw_chains_mapping(esw), fdb_chain->id);

+	return err;

+}

+

 static struct fdb_chain *

 mlx5_esw_chains_create_fdb_chain(struct mlx5_eswitch *esw, u32 chain)

 {

@@ -272,6 +343,10 @@ mlx5_esw_chains_create_fdb_chain(struct mlx5_eswitch *esw, u32 chain)

 	fdb_chain->chain = chain;

 	INIT_LIST_HEAD(&fdb_chain->prios_list);

+	err = create_fdb_chain_restore(fdb_chain);

+	if (err)

+		goto err_restore;

+

 	err = rhashtable_insert_fast(&esw_chains_ht(esw), &fdb_chain->node,

 				     chain_params);

 	if (err)

@@ -280,6 +355,12 @@ mlx5_esw_chains_create_fdb_chain(struct mlx5_eswitch *esw, u32 chain)

 	return fdb_chain;

 err_insert:

+	if (fdb_chain->chain != mlx5_esw_chains_get_ft_chain(esw)) {

+		mlx5_del_flow_rules(fdb_chain->restore_rule);

+		mlx5_modify_header_dealloc(esw->dev,

+					   fdb_chain->miss_modify_hdr);

+	}

+err_restore:

 	kvfree(fdb_chain);

 	return ERR_PTR(err);

 }

@@ -291,6 +372,15 @@ mlx5_esw_chains_destroy_fdb_chain(struct fdb_chain *fdb_chain)

 	rhashtable_remove_fast(&esw_chains_ht(esw), &fdb_chain->node,

 			       chain_params);

+

+	if (fdb_chain->chain != mlx5_esw_chains_get_ft_chain(esw)) {

+		mlx5_del_flow_rules(fdb_chain->restore_rule);

+		mlx5_modify_header_dealloc(esw->dev,

+					   fdb_chain->miss_modify_hdr);

+

+		mapping_remove(esw_chains_mapping(esw), fdb_chain->id);

+	}

+

 	kvfree(fdb_chain);

 }

@@ -313,10 +403,12 @@ mlx5_esw_chains_get_fdb_chain(struct mlx5_eswitch *esw, u32 chain)

 }

 static struct mlx5_flow_handle *

-mlx5_esw_chains_add_miss_rule(struct mlx5_flow_table *fdb,

+mlx5_esw_chains_add_miss_rule(struct fdb_chain *fdb_chain,

+			      struct mlx5_flow_table *fdb,

 			      struct mlx5_flow_table *next_fdb)

 {

 	static const struct mlx5_flow_spec spec = {};

+	struct mlx5_eswitch *esw = fdb_chain->esw;

 	struct mlx5_flow_destination dest = {};

 	struct mlx5_flow_act act = {};

@@ -325,6 +417,11 @@ mlx5_esw_chains_add_miss_rule(struct mlx5_flow_table *fdb,

 	dest.type  = MLX5_FLOW_DESTINATION_TYPE_FLOW_TABLE;

 	dest.ft = next_fdb;

+	if (fdb_chain->chain != mlx5_esw_chains_get_ft_chain(esw)) {

+		act.modify_hdr = fdb_chain->miss_modify_hdr;

+		act.action |= MLX5_FLOW_CONTEXT_ACTION_MOD_HDR;

+	}

+

 	return mlx5_add_flow_rules(fdb, &spec, &act, &dest, 1);

 }

@@ -348,7 +445,8 @@ mlx5_esw_chains_update_prio_prevs(struct fdb_prio *fdb_prio,

 	list_for_each_entry_continue_reverse(pos,

 					     &fdb_chain->prios_list,

 					     list) {

-		miss_rules[n] = mlx5_esw_chains_add_miss_rule(pos->fdb,

+		miss_rules[n] = mlx5_esw_chains_add_miss_rule(fdb_chain,

+							      pos->fdb,

 							      next_fdb);

 		if (IS_ERR(miss_rules[n])) {

 			err = PTR_ERR(miss_rules[n]);

@@ -462,7 +560,7 @@ mlx5_esw_chains_create_fdb_prio(struct mlx5_eswitch *esw,

 	}

 	/* Add miss rule to next_fdb */

-	miss_rule = mlx5_esw_chains_add_miss_rule(fdb, next_fdb);

+	miss_rule = mlx5_esw_chains_add_miss_rule(fdb_chain, fdb, next_fdb);

 	if (IS_ERR(miss_rule)) {

 		err = PTR_ERR(miss_rule);

 		goto err_miss_rule;

@@ -627,6 +725,7 @@ mlx5_esw_chains_init(struct mlx5_eswitch *esw)

 	struct mlx5_esw_chains_priv *chains_priv;

 	struct mlx5_core_dev *dev = esw->dev;

 	u32 max_flow_counter, fdb_max;

+	struct mapping_ctx *mapping;

 	int err;

 	chains_priv = kzalloc(sizeof(*chains_priv), GFP_KERNEL);

@@ -663,10 +762,20 @@ mlx5_esw_chains_init(struct mlx5_eswitch *esw)

 	if (err)

 		goto init_prios_ht_err;

+	mapping = mapping_create(sizeof(u32), esw_get_max_restore_tag(esw),

+				 true);

+	if (IS_ERR(mapping)) {

+		err = PTR_ERR(mapping);

+		goto mapping_err;

+	}

+	esw_chains_mapping(esw) = mapping;

+

 	mutex_init(&esw_chains_lock(esw));

 	return 0;

+mapping_err:

+	rhashtable_destroy(&esw_prios_ht(esw));

 init_prios_ht_err:

 	rhashtable_destroy(&esw_chains_ht(esw));

 init_chains_ht_err:

@@ -678,6 +787,7 @@ static void

 mlx5_esw_chains_cleanup(struct mlx5_eswitch *esw)

 {

 	mutex_destroy(&esw_chains_lock(esw));

+	mapping_destroy(esw_chains_mapping(esw));

 	rhashtable_destroy(&esw_prios_ht(esw));

 	rhashtable_destroy(&esw_chains_ht(esw));

@@ -756,3 +866,17 @@ mlx5_esw_chains_destroy(struct mlx5_eswitch *esw)

 	mlx5_esw_chains_close(esw);

 	mlx5_esw_chains_cleanup(esw);

 }

+

+int mlx5_eswitch_get_chain_for_tag(struct mlx5_eswitch *esw, u32 tag,

+				   u32 *chain)

+{

+	int err;

+

+	err = mapping_find(esw_chains_mapping(esw), tag, chain);

+	if (err) {

+		esw_warn(esw->dev, "Can't find chain for tag: %d\n", tag);

+		return -ENOENT;

+	}

+

+	return 0;

+}

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads_chains.h b/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads_chains.h

index 4ae2baf2a7a1..e806d8de868e 100644

--- a/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads_chains.h

+++ b/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads_chains.h

@@ -28,5 +28,7 @@ mlx5_esw_chains_get_tc_end_ft(struct mlx5_eswitch *esw);

 int mlx5_esw_chains_create(struct mlx5_eswitch *esw);

 void mlx5_esw_chains_destroy(struct mlx5_eswitch *esw);

-#endif /* __ML5_ESW_CHAINS_H__ */

+int

+mlx5_eswitch_get_chain_for_tag(struct mlx5_eswitch *esw, u32 tag, u32 *chain);

+#endif /* __ML5_ESW_CHAINS_H__ */

-- 

2.13.6