[PATCH net-next 3/4] mlxsw: spectrum_acl: Adapt ACL configuration to new firmware versions

[Ido Schimmel <idosch@mellanox.com>]

The driver currently creates empty ACL groups, binds them to the
requested port and then fills them with actual ACLs that point to TCAM
regions.

However, empty ACL groups are considered invalid and upcoming firmware
versions are going to forbid their binding.

Work around this limitation by only performing the binding after the
first ACL was added to the group.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
---
 drivers/net/ethernet/mellanox/mlxsw/spectrum_acl.c | 43 +++++++++++++---------
 1 file changed, 26 insertions(+), 17 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl.c
index 21ed27ae51e3..1c1601a43978 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl.c
@@ -160,6 +160,13 @@ bool mlxsw_sp_acl_block_disabled(struct mlxsw_sp_acl_block *block)
 	return block->disable_count;
 }
 
+static bool
+mlxsw_sp_acl_ruleset_is_singular(const struct mlxsw_sp_acl_ruleset *ruleset)
+{
+	/* We hold a reference on ruleset ourselves */
+	return ruleset->ref_count == 2;
+}
+
 static int
 mlxsw_sp_acl_ruleset_bind(struct mlxsw_sp *mlxsw_sp,
 			  struct mlxsw_sp_acl_block *block,
@@ -341,21 +348,8 @@ mlxsw_sp_acl_ruleset_create(struct mlxsw_sp *mlxsw_sp,
 	if (err)
 		goto err_ht_insert;
 
-	if (!chain_index) {
-		/* We only need ruleset with chain index 0, the implicit one,
-		 * to be directly bound to device. The rest of the rulesets
-		 * are bound by "Goto action set".
-		 */
-		err = mlxsw_sp_acl_ruleset_block_bind(mlxsw_sp, ruleset, block);
-		if (err)
-			goto err_ruleset_bind;
-	}
-
 	return ruleset;
 
-err_ruleset_bind:
-	rhashtable_remove_fast(&acl->ruleset_ht, &ruleset->ht_node,
-			       mlxsw_sp_acl_ruleset_ht_params);
 err_ht_insert:
 	ops->ruleset_del(mlxsw_sp, ruleset->priv);
 err_ops_ruleset_add:
@@ -369,12 +363,8 @@ static void mlxsw_sp_acl_ruleset_destroy(struct mlxsw_sp *mlxsw_sp,
 					 struct mlxsw_sp_acl_ruleset *ruleset)
 {
 	const struct mlxsw_sp_acl_profile_ops *ops = ruleset->ht_key.ops;
-	struct mlxsw_sp_acl_block *block = ruleset->ht_key.block;
-	u32 chain_index = ruleset->ht_key.chain_index;
 	struct mlxsw_sp_acl *acl = mlxsw_sp->acl;
 
-	if (!chain_index)
-		mlxsw_sp_acl_ruleset_block_unbind(mlxsw_sp, ruleset, block);
 	rhashtable_remove_fast(&acl->ruleset_ht, &ruleset->ht_node,
 			       mlxsw_sp_acl_ruleset_ht_params);
 	ops->ruleset_del(mlxsw_sp, ruleset->priv);
@@ -688,10 +678,25 @@ int mlxsw_sp_acl_rule_add(struct mlxsw_sp *mlxsw_sp,
 	if (err)
 		goto err_rhashtable_insert;
 
+	if (!ruleset->ht_key.chain_index &&
+	    mlxsw_sp_acl_ruleset_is_singular(ruleset)) {
+		/* We only need ruleset with chain index 0, the implicit
+		 * one, to be directly bound to device. The rest of the
+		 * rulesets are bound by "Goto action set".
+		 */
+		err = mlxsw_sp_acl_ruleset_block_bind(mlxsw_sp, ruleset,
+						      ruleset->ht_key.block);
+		if (err)
+			goto err_ruleset_block_bind;
+	}
+
 	list_add_tail(&rule->list, &mlxsw_sp->acl->rules);
 	ruleset->ht_key.block->rule_count++;
 	return 0;
 
+err_ruleset_block_bind:
+	rhashtable_remove_fast(&ruleset->rule_ht, &rule->ht_node,
+			       mlxsw_sp_acl_rule_ht_params);
 err_rhashtable_insert:
 	ops->rule_del(mlxsw_sp, rule->priv);
 	return err;
@@ -705,6 +710,10 @@ void mlxsw_sp_acl_rule_del(struct mlxsw_sp *mlxsw_sp,
 
 	ruleset->ht_key.block->rule_count--;
 	list_del(&rule->list);
+	if (!ruleset->ht_key.chain_index &&
+	    mlxsw_sp_acl_ruleset_is_singular(ruleset))
+		mlxsw_sp_acl_ruleset_block_unbind(mlxsw_sp, ruleset,
+						  ruleset->ht_key.block);
 	rhashtable_remove_fast(&ruleset->rule_ht, &rule->ht_node,
 			       mlxsw_sp_acl_rule_ht_params);
 	ops->rule_del(mlxsw_sp, rule->priv);
-- 
2.14.3