net/mlx5: E-Switch, Refactor chains and priorities

To support the entire chain and prio range (32bit + 16bit),
instead of a using a static array of chains/prios of limited size, create
them dynamically, and use a rhashtable to search for existing chains/prio
combinations.

This will be used in next patch to actually increase the number using
unamanged tables support and ignore flow level capability.

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>

1 files changed, 542 insertions, 0 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads_chains.c b/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads_chains.c
new file mode 100644
index 000000000000..a694cc52d94c
--- /dev/null
+++ b/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads_chains.c
@@ -0,0 +1,542 @@
+// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
+// Copyright (c) 2020 Mellanox Technologies.
+
+#include <linux/mlx5/driver.h>
+#include <linux/mlx5/mlx5_ifc.h>
+#include <linux/mlx5/fs.h>
+
+#include "eswitch_offloads_chains.h"
+#include "mlx5_core.h"
+#include "fs_core.h"
+#include "eswitch.h"
+#include "en.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_prios_ht(esw) (esw_chains_priv(esw)->prios_ht)
+#define fdb_pool_left(esw) (esw_chains_priv(esw)->fdb_left)
+
+#define ESW_OFFLOADS_NUM_GROUPS  4
+
+/* Firmware currently has 4 pool of 4 sizes that it supports (ESW_POOLS),
+ * and a virtual memory region of 16M (ESW_SIZE), this region is duplicated
+ * for each flow table pool. We can allocate up to 16M of each pool,
+ * and we keep track of how much we used via get_next_avail_sz_from_pool.
+ * Firmware doesn't report any of this for now.
+ * ESW_POOL is expected to be sorted from large to small and match firmware
+ * pools.
+ */
+#define ESW_SIZE (16 * 1024 * 1024)
+const unsigned int ESW_POOLS[] = { 4 * 1024 * 1024,
+				   1 * 1024 * 1024,
+				   64 * 1024,
+				   4 * 1024, };
+
+struct mlx5_esw_chains_priv {
+	struct rhashtable chains_ht;
+	struct rhashtable prios_ht;
+	/* Protects above chains_ht and prios_ht */
+	struct mutex lock;
+
+	int fdb_left[ARRAY_SIZE(ESW_POOLS)];
+};
+
+struct fdb_chain {
+	struct rhash_head node;
+
+	u32 chain;
+
+	int ref;
+
+	struct mlx5_eswitch *esw;
+};
+
+struct fdb_prio_key {
+	u32 chain;
+	u32 prio;
+	u32 level;
+};
+
+struct fdb_prio {
+	struct rhash_head node;
+
+	struct fdb_prio_key key;
+
+	int ref;
+
+	struct fdb_chain *fdb_chain;
+	struct mlx5_flow_table *fdb;
+};
+
+static const struct rhashtable_params chain_params = {
+	.head_offset = offsetof(struct fdb_chain, node),
+	.key_offset = offsetof(struct fdb_chain, chain),
+	.key_len = sizeof_field(struct fdb_chain, chain),
+	.automatic_shrinking = true,
+};
+
+static const struct rhashtable_params prio_params = {
+	.head_offset = offsetof(struct fdb_prio, node),
+	.key_offset = offsetof(struct fdb_prio, key),
+	.key_len = sizeof_field(struct fdb_prio, key),
+	.automatic_shrinking = true,
+};
+
+bool mlx5_esw_chains_prios_supported(struct mlx5_eswitch *esw)
+{
+	return esw->fdb_table.flags & ESW_FDB_CHAINS_AND_PRIOS_SUPPORTED;
+}
+
+u32 mlx5_esw_chains_get_chain_range(struct mlx5_eswitch *esw)
+{
+	if (!mlx5_esw_chains_prios_supported(esw))
+		return 1;
+
+	return FDB_TC_MAX_CHAIN;
+}
+
+u32 mlx5_esw_chains_get_ft_chain(struct mlx5_eswitch *esw)
+{
+	return mlx5_esw_chains_get_chain_range(esw) + 1;
+}
+
+u32 mlx5_esw_chains_get_prio_range(struct mlx5_eswitch *esw)
+{
+	if (!mlx5_esw_chains_prios_supported(esw))
+		return 1;
+
+	return FDB_TC_MAX_PRIO;
+}
+
+static unsigned int mlx5_esw_chains_get_level_range(struct mlx5_eswitch *esw)
+{
+	return FDB_TC_LEVELS_PER_PRIO;
+}
+
+#define POOL_NEXT_SIZE 0
+static int
+mlx5_esw_chains_get_avail_sz_from_pool(struct mlx5_eswitch *esw,
+				       int desired_size)
+{
+	int i, found_i = -1;
+
+	for (i = ARRAY_SIZE(ESW_POOLS) - 1; i >= 0; i--) {
+		if (fdb_pool_left(esw)[i] && ESW_POOLS[i] > desired_size) {
+			found_i = i;
+			if (desired_size != POOL_NEXT_SIZE)
+				break;
+		}
+	}
+
+	if (found_i != -1) {
+		--fdb_pool_left(esw)[found_i];
+		return ESW_POOLS[found_i];
+	}
+
+	return 0;
+}
+
+static void
+mlx5_esw_chains_put_sz_to_pool(struct mlx5_eswitch *esw, int sz)
+{
+	int i;
+
+	for (i = ARRAY_SIZE(ESW_POOLS) - 1; i >= 0; i--) {
+		if (sz == ESW_POOLS[i]) {
+			++fdb_pool_left(esw)[i];
+			return;
+		}
+	}
+
+	WARN_ONCE(1, "Couldn't find size %d in fdb size pool", sz);
+}
+
+static void
+mlx5_esw_chains_init_sz_pool(struct mlx5_eswitch *esw)
+{
+	u32 fdb_max;
+	int i;
+
+	fdb_max = 1 << MLX5_CAP_ESW_FLOWTABLE_FDB(esw->dev, log_max_ft_size);
+
+	for (i = ARRAY_SIZE(ESW_POOLS) - 1; i >= 0; i--)
+		fdb_pool_left(esw)[i] =
+			ESW_POOLS[i] <= fdb_max ? ESW_SIZE / ESW_POOLS[i] : 0;
+}
+
+static struct mlx5_flow_table *
+mlx5_esw_chains_create_fdb_table(struct mlx5_eswitch *esw,
+				 u32 chain, u32 prio, u32 level)
+{
+	struct mlx5_flow_table_attr ft_attr = {};
+	struct mlx5_flow_namespace *ns;
+	struct mlx5_flow_table *fdb;
+	int sz;
+
+	if (esw->offloads.encap != DEVLINK_ESWITCH_ENCAP_MODE_NONE)
+		ft_attr.flags |= (MLX5_FLOW_TABLE_TUNNEL_EN_REFORMAT |
+				  MLX5_FLOW_TABLE_TUNNEL_EN_DECAP);
+
+	sz = mlx5_esw_chains_get_avail_sz_from_pool(esw, POOL_NEXT_SIZE);
+	if (!sz)
+		return ERR_PTR(-ENOSPC);
+
+	ft_attr.max_fte = sz;
+	ft_attr.level = level;
+	ft_attr.prio = prio - 1;
+	ft_attr.autogroup.max_num_groups = ESW_OFFLOADS_NUM_GROUPS;
+	ns = mlx5_get_fdb_sub_ns(esw->dev, chain);
+
+	fdb = mlx5_create_auto_grouped_flow_table(ns, &ft_attr);
+	if (IS_ERR(fdb)) {
+		esw_warn(esw->dev,
+			 "Failed to create FDB table err %d (chain: %d, prio: %d, level: %d, size: %d)\n",
+			 (int)PTR_ERR(fdb), chain, prio, level, sz);
+		mlx5_esw_chains_put_sz_to_pool(esw, sz);
+		return fdb;
+	}
+
+	return fdb;
+}
+
+static void
+mlx5_esw_chains_destroy_fdb_table(struct mlx5_eswitch *esw,
+				  struct mlx5_flow_table *fdb)
+{
+	mlx5_esw_chains_put_sz_to_pool(esw, fdb->max_fte);
+	mlx5_destroy_flow_table(fdb);
+}
+
+static struct fdb_chain *
+mlx5_esw_chains_create_fdb_chain(struct mlx5_eswitch *esw, u32 chain)
+{
+	struct fdb_chain *fdb_chain = NULL;
+	int err;
+
+	fdb_chain = kvzalloc(sizeof(*fdb_chain), GFP_KERNEL);
+	if (!fdb_chain)
+		return ERR_PTR(-ENOMEM);
+
+	fdb_chain->esw = esw;
+	fdb_chain->chain = chain;
+
+	err = rhashtable_insert_fast(&esw_chains_ht(esw), &fdb_chain->node,
+				     chain_params);
+	if (err)
+		goto err_insert;
+
+	return fdb_chain;
+
+err_insert:
+	kvfree(fdb_chain);
+	return ERR_PTR(err);
+}
+
+static void
+mlx5_esw_chains_destroy_fdb_chain(struct fdb_chain *fdb_chain)
+{
+	struct mlx5_eswitch *esw = fdb_chain->esw;
+
+	rhashtable_remove_fast(&esw_chains_ht(esw), &fdb_chain->node,
+			       chain_params);
+	kvfree(fdb_chain);
+}
+
+static struct fdb_chain *
+mlx5_esw_chains_get_fdb_chain(struct mlx5_eswitch *esw, u32 chain)
+{
+	struct fdb_chain *fdb_chain;
+
+	fdb_chain = rhashtable_lookup_fast(&esw_chains_ht(esw), &chain,
+					   chain_params);
+	if (!fdb_chain) {
+		fdb_chain = mlx5_esw_chains_create_fdb_chain(esw, chain);
+		if (IS_ERR(fdb_chain))
+			return fdb_chain;
+	}
+
+	fdb_chain->ref++;
+
+	return fdb_chain;
+}
+
+static void
+mlx5_esw_chains_put_fdb_chain(struct fdb_chain *fdb_chain)
+{
+	if (--fdb_chain->ref == 0)
+		mlx5_esw_chains_destroy_fdb_chain(fdb_chain);
+}
+
+static struct fdb_prio *
+mlx5_esw_chains_create_fdb_prio(struct mlx5_eswitch *esw,
+				u32 chain, u32 prio, u32 level)
+{
+	struct fdb_prio *fdb_prio = NULL;
+	struct fdb_chain *fdb_chain;
+	struct mlx5_flow_table *fdb;
+	int err;
+
+	fdb_chain = mlx5_esw_chains_get_fdb_chain(esw, chain);
+	if (IS_ERR(fdb_chain))
+		return ERR_CAST(fdb_chain);
+
+	fdb_prio = kvzalloc(sizeof(*fdb_prio), GFP_KERNEL);
+	if (!fdb_prio) {
+		err = -ENOMEM;
+		goto err_alloc;
+	}
+
+	fdb = mlx5_esw_chains_create_fdb_table(esw, fdb_chain->chain, prio,
+					       level);
+	if (IS_ERR(fdb)) {
+		err = PTR_ERR(fdb);
+		goto err_create;
+	}
+
+	fdb_prio->fdb_chain = fdb_chain;
+	fdb_prio->key.chain = chain;
+	fdb_prio->key.prio = prio;
+	fdb_prio->key.level = level;
+	fdb_prio->fdb = fdb;
+
+	err = rhashtable_insert_fast(&esw_prios_ht(esw), &fdb_prio->node,
+				     prio_params);
+	if (err)
+		goto err_insert;
+
+	return fdb_prio;
+
+err_insert:
+	mlx5_esw_chains_destroy_fdb_table(esw, fdb);
+err_create:
+	kvfree(fdb_prio);
+err_alloc:
+	mlx5_esw_chains_put_fdb_chain(fdb_chain);
+	return ERR_PTR(err);
+}
+
+static void
+mlx5_esw_chains_destroy_fdb_prio(struct mlx5_eswitch *esw,
+				 struct fdb_prio *fdb_prio)
+{
+	struct fdb_chain *fdb_chain = fdb_prio->fdb_chain;
+
+	rhashtable_remove_fast(&esw_prios_ht(esw), &fdb_prio->node,
+			       prio_params);
+	mlx5_esw_chains_destroy_fdb_table(esw, fdb_prio->fdb);
+	mlx5_esw_chains_put_fdb_chain(fdb_chain);
+	kvfree(fdb_prio);
+}
+
+struct mlx5_flow_table *
+mlx5_esw_chains_get_table(struct mlx5_eswitch *esw, u32 chain, u32 prio,
+			  u32 level)
+{
+	struct mlx5_flow_table *prev_fts;
+	struct fdb_prio *fdb_prio;
+	struct fdb_prio_key key;
+	int l = 0;
+
+	if ((chain > mlx5_esw_chains_get_chain_range(esw) &&
+	     chain != mlx5_esw_chains_get_ft_chain(esw)) ||
+	    prio > mlx5_esw_chains_get_prio_range(esw) ||
+	    level > mlx5_esw_chains_get_level_range(esw))
+		return ERR_PTR(-EOPNOTSUPP);
+
+	/* create earlier levels for correct fs_core lookup when
+	 * connecting tables.
+	 */
+	for (l = 0; l < level; l++) {
+		prev_fts = mlx5_esw_chains_get_table(esw, chain, prio, l);
+		if (IS_ERR(prev_fts)) {
+			fdb_prio = ERR_CAST(prev_fts);
+			goto err_get_prevs;
+		}
+	}
+
+	key.chain = chain;
+	key.prio = prio;
+	key.level = level;
+
+	mutex_lock(&esw_chains_lock(esw));
+	fdb_prio = rhashtable_lookup_fast(&esw_prios_ht(esw), &key,
+					  prio_params);
+	if (!fdb_prio) {
+		fdb_prio = mlx5_esw_chains_create_fdb_prio(esw, chain,
+							   prio, level);
+		if (IS_ERR(fdb_prio))
+			goto err_create_prio;
+	}
+
+	++fdb_prio->ref;
+	mutex_unlock(&esw_chains_lock(esw));
+
+	return fdb_prio->fdb;
+
+err_create_prio:
+	mutex_unlock(&esw_chains_lock(esw));
+err_get_prevs:
+	while (--l >= 0)
+		mlx5_esw_chains_put_table(esw, chain, prio, l);
+	return ERR_CAST(fdb_prio);
+}
+
+void
+mlx5_esw_chains_put_table(struct mlx5_eswitch *esw, u32 chain, u32 prio,
+			  u32 level)
+{
+	struct fdb_prio *fdb_prio;
+	struct fdb_prio_key key;
+
+	key.chain = chain;
+	key.prio = prio;
+	key.level = level;
+
+	mutex_lock(&esw_chains_lock(esw));
+	fdb_prio = rhashtable_lookup_fast(&esw_prios_ht(esw), &key,
+					  prio_params);
+	if (!fdb_prio)
+		goto err_get_prio;
+
+	if (--fdb_prio->ref == 0)
+		mlx5_esw_chains_destroy_fdb_prio(esw, fdb_prio);
+	mutex_unlock(&esw_chains_lock(esw));
+
+	while (level-- > 0)
+		mlx5_esw_chains_put_table(esw, chain, prio, level);
+
+	return;
+
+err_get_prio:
+	mutex_unlock(&esw_chains_lock(esw));
+	WARN_ONCE(1,
+		  "Couldn't find table: (chain: %d prio: %d level: %d)",
+		  chain, prio, level);
+}
+
+static int
+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;
+	int err;
+
+	chains_priv = kzalloc(sizeof(*chains_priv), GFP_KERNEL);
+	if (!chains_priv)
+		return -ENOMEM;
+	esw_chains_priv(esw) = chains_priv;
+
+	max_flow_counter = (MLX5_CAP_GEN(dev, max_flow_counter_31_16) << 16) |
+			    MLX5_CAP_GEN(dev, max_flow_counter_15_0);
+	fdb_max = 1 << MLX5_CAP_ESW_FLOWTABLE_FDB(dev, log_max_ft_size);
+
+	esw_debug(dev,
+		  "Init esw offloads chains, max counters(%d), groups(%d), max flow table size(%d)\n",
+		  max_flow_counter, ESW_OFFLOADS_NUM_GROUPS, fdb_max);
+
+	mlx5_esw_chains_init_sz_pool(esw);
+
+	if (!MLX5_CAP_ESW_FLOWTABLE(esw->dev, multi_fdb_encap) &&
+	    esw->offloads.encap != DEVLINK_ESWITCH_ENCAP_MODE_NONE) {
+		esw->fdb_table.flags &= ~ESW_FDB_CHAINS_AND_PRIOS_SUPPORTED;
+		esw_warn(dev, "Tc chains and priorities offload aren't supported, update firmware if needed\n");
+	} else {
+		esw->fdb_table.flags |= ESW_FDB_CHAINS_AND_PRIOS_SUPPORTED;
+		esw_info(dev, "Supported tc offload range - chains: %u, prios: %u\n",
+			 mlx5_esw_chains_get_chain_range(esw),
+			 mlx5_esw_chains_get_prio_range(esw));
+	}
+
+	err = rhashtable_init(&esw_chains_ht(esw), &chain_params);
+	if (err)
+		goto init_chains_ht_err;
+
+	err = rhashtable_init(&esw_prios_ht(esw), &prio_params);
+	if (err)
+		goto init_prios_ht_err;
+
+	mutex_init(&esw_chains_lock(esw));
+
+	return 0;
+
+init_prios_ht_err:
+	rhashtable_destroy(&esw_chains_ht(esw));
+init_chains_ht_err:
+	kfree(chains_priv);
+	return err;
+}
+
+static void
+mlx5_esw_chains_cleanup(struct mlx5_eswitch *esw)
+{
+	mutex_destroy(&esw_chains_lock(esw));
+	rhashtable_destroy(&esw_prios_ht(esw));
+	rhashtable_destroy(&esw_chains_ht(esw));
+
+	kfree(esw_chains_priv(esw));
+}
+
+static int
+mlx5_esw_chains_open(struct mlx5_eswitch *esw)
+{
+	struct mlx5_flow_table *ft;
+	int err;
+
+	/* Always open the root for fast path */
+	ft = mlx5_esw_chains_get_table(esw, 0, 1, 0);
+	if (IS_ERR(ft))
+		return PTR_ERR(ft);
+
+	/* Open level 1 for split rules now if prios isn't supported  */
+	if (!mlx5_esw_chains_prios_supported(esw)) {
+		ft = mlx5_esw_chains_get_table(esw, 0, 1, 1);
+
+		if (IS_ERR(ft)) {
+			err = PTR_ERR(ft);
+			goto level_1_err;
+		}
+	}
+
+	return 0;
+
+level_1_err:
+	mlx5_esw_chains_put_table(esw, 0, 1, 0);
+	return err;
+}
+
+static void
+mlx5_esw_chains_close(struct mlx5_eswitch *esw)
+{
+	if (!mlx5_esw_chains_prios_supported(esw))
+		mlx5_esw_chains_put_table(esw, 0, 1, 1);
+	mlx5_esw_chains_put_table(esw, 0, 1, 0);
+}
+
+int
+mlx5_esw_chains_create(struct mlx5_eswitch *esw)
+{
+	int err;
+
+	err = mlx5_esw_chains_init(esw);
+	if (err)
+		return err;
+
+	err = mlx5_esw_chains_open(esw);
+	if (err)
+		goto err_open;
+
+	return 0;
+
+err_open:
+	mlx5_esw_chains_cleanup(esw);
+	return err;
+}
+
+void
+mlx5_esw_chains_destroy(struct mlx5_eswitch *esw)
+{
+	mlx5_esw_chains_close(esw);
+	mlx5_esw_chains_cleanup(esw);
+}