mlxsw: spectrum_acl: Include delta bits into hashtable key

Currently only ERP mask masked bits in key are considered for
the hashtable key. That leads to false negative collisions
and fallbacks to C-TCAM in case two keys differ only in delta bits.

Fix this by taking full encoded key as a hashtable key,
including delta bits.
Reported-by: Nir Dotan <nird@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlxsw/spectrum_acl_atcam.c

@@ -390,8 +390,7 @@ mlxsw_sp_acl_atcam_region_entry_insert(struct mlxsw_sp *mlxsw_sp,
 	if (err)
 		return err;
 
-	lkey_id = aregion->ops->lkey_id_get(aregion, aentry->ht_key.enc_key,
-					    erp_id);
+	lkey_id = aregion->ops->lkey_id_get(aregion, aentry->enc_key, erp_id);
 	if (IS_ERR(lkey_id))
 		return PTR_ERR(lkey_id);
 	aentry->lkey_id = lkey_id;
@@ -399,7 +398,7 @@ mlxsw_sp_acl_atcam_region_entry_insert(struct mlxsw_sp *mlxsw_sp,
 	kvdl_index = mlxsw_afa_block_first_kvdl_index(rulei->act_block);
 	mlxsw_reg_ptce3_pack(ptce3_pl, true, MLXSW_REG_PTCE3_OP_WRITE_WRITE,
 			     priority, region->tcam_region_info,
-			     aentry->ht_key.enc_key, erp_id,
+			     aentry->enc_key, erp_id,
 			     aentry->delta_info.start,
 			     aentry->delta_info.mask,
 			     aentry->delta_info.value,
@@ -424,12 +423,11 @@ mlxsw_sp_acl_atcam_region_entry_remove(struct mlxsw_sp *mlxsw_sp,
 	struct mlxsw_sp_acl_atcam_lkey_id *lkey_id = aentry->lkey_id;
 	struct mlxsw_sp_acl_tcam_region *region = aregion->region;
 	u8 erp_id = mlxsw_sp_acl_erp_mask_erp_id(aentry->erp_mask);
-	char *enc_key = aentry->ht_key.enc_key;
 	char ptce3_pl[MLXSW_REG_PTCE3_LEN];
 
 	mlxsw_reg_ptce3_pack(ptce3_pl, false, MLXSW_REG_PTCE3_OP_WRITE_WRITE, 0,
 			     region->tcam_region_info,
-			     enc_key, erp_id,
+			     aentry->enc_key, erp_id,
 			     aentry->delta_info.start,
 			     aentry->delta_info.mask,
 			     aentry->delta_info.value,
@@ -458,7 +456,7 @@ mlxsw_sp_acl_atcam_region_entry_action_replace(struct mlxsw_sp *mlxsw_sp,
 	kvdl_index = mlxsw_afa_block_first_kvdl_index(rulei->act_block);
 	mlxsw_reg_ptce3_pack(ptce3_pl, true, MLXSW_REG_PTCE3_OP_WRITE_UPDATE,
 			     priority, region->tcam_region_info,
-			     aentry->ht_key.enc_key, erp_id,
+			     aentry->enc_key, erp_id,
 			     aentry->delta_info.start,
 			     aentry->delta_info.mask,
 			     aentry->delta_info.value,
@@ -481,15 +479,15 @@ __mlxsw_sp_acl_atcam_entry_add(struct mlxsw_sp *mlxsw_sp,
 	int err;
 
 	mlxsw_afk_encode(afk, region->key_info, &rulei->values,
-			 aentry->full_enc_key, mask);
+			 aentry->ht_key.full_enc_key, mask);
 
 	erp_mask = mlxsw_sp_acl_erp_mask_get(aregion, mask, false);
 	if (IS_ERR(erp_mask))
 		return PTR_ERR(erp_mask);
 	aentry->erp_mask = erp_mask;
 	aentry->ht_key.erp_id = mlxsw_sp_acl_erp_mask_erp_id(erp_mask);
-	memcpy(aentry->ht_key.enc_key, aentry->full_enc_key,
-	       sizeof(aentry->ht_key.enc_key));
+	memcpy(aentry->enc_key, aentry->ht_key.full_enc_key,
+	       sizeof(aentry->enc_key));
 
 	/* Compute all needed delta information and clear the delta bits
 	 * from the encrypted key.
@@ -498,8 +496,9 @@ __mlxsw_sp_acl_atcam_entry_add(struct mlxsw_sp *mlxsw_sp,
 	aentry->delta_info.start = mlxsw_sp_acl_erp_delta_start(delta);
 	aentry->delta_info.mask = mlxsw_sp_acl_erp_delta_mask(delta);
 	aentry->delta_info.value =
-		mlxsw_sp_acl_erp_delta_value(delta, aentry->full_enc_key);
-	mlxsw_sp_acl_erp_delta_clear(delta, aentry->ht_key.enc_key);
+		mlxsw_sp_acl_erp_delta_value(delta,
+					     aentry->ht_key.full_enc_key);
+	mlxsw_sp_acl_erp_delta_clear(delta, aentry->enc_key);
 
 	/* Add rule to the list of A-TCAM rules, assuming this
 	 * rule is intended to A-TCAM. In case this rule does

drivers/net/ethernet/mellanox/mlxsw/spectrum_acl_bloom_filter.c

@@ -133,7 +133,7 @@ mlxsw_sp_acl_bf_key_encode(struct mlxsw_sp_acl_atcam_region *aregion,
 		memcpy(chunk + MLXSW_BLOOM_CHUNK_PAD_BYTES, &erp_region_id,
 		       sizeof(erp_region_id));
 		memcpy(chunk + MLXSW_BLOOM_CHUNK_KEY_OFFSET,
-		       &aentry->ht_key.enc_key[chunk_key_offsets[chunk_index]],
+		       &aentry->enc_key[chunk_key_offsets[chunk_index]],
 		       MLXSW_BLOOM_CHUNK_KEY_BYTES);
 		chunk += MLXSW_BLOOM_KEY_CHUNK_BYTES;
 	}

drivers/net/ethernet/mellanox/mlxsw/spectrum_acl_tcam.h

@@ -161,9 +161,9 @@ struct mlxsw_sp_acl_atcam_region {
 };
 
 struct mlxsw_sp_acl_atcam_entry_ht_key {
-	char enc_key[MLXSW_REG_PTCEX_FLEX_KEY_BLOCKS_LEN]; /* Encoded key,
-							    * minus delta bits.
-							    */
+	char full_enc_key[MLXSW_REG_PTCEX_FLEX_KEY_BLOCKS_LEN]; /* Encoded
+								 * key.
+								 */
 	u8 erp_id;
 };
 
@@ -175,7 +175,9 @@ struct mlxsw_sp_acl_atcam_entry {
 	struct rhash_head ht_node;
 	struct list_head list; /* Member in entries_list */
 	struct mlxsw_sp_acl_atcam_entry_ht_key ht_key;
-	char full_enc_key[MLXSW_REG_PTCEX_FLEX_KEY_BLOCKS_LEN]; /* Encoded key */
+	char enc_key[MLXSW_REG_PTCEX_FLEX_KEY_BLOCKS_LEN]; /* Encoded key,
+							    * minus delta bits.
+							    */
 	struct {
 		u16 start;
 		u8 mask;