From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4B06BC433FE for ; Fri, 7 Jan 2022 00:58:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344905AbiAGA64 (ORCPT ); Thu, 6 Jan 2022 19:58:56 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60094 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344883AbiAGA6r (ORCPT ); Thu, 6 Jan 2022 19:58:47 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BCC1DC0611FD for ; Thu, 6 Jan 2022 16:58:47 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 59DF761EAB for ; Fri, 7 Jan 2022 00:58:47 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BDBA0C36AF6; Fri, 7 Jan 2022 00:58:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1641517127; bh=5jD1OzQ5f7jM99gGeK9vAw2XeqxWy8Ppmlr0pVBeQV0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Qp3MiyNZJ4WtdK7PdT02l+MM90LsqHaIYpAYm/8VRb+CmIgqyv9eBlCoIwtLzYiMC md2kuyZOlVSQ2o4HpuCD6o/XRgDK9OhH713sP9jTSGqQSvBprJMC/H0BWGsdPBrDNW DX9OI7Y/dxVQzsJaXISV9W4JNPx3GqkzSsYbDgbsQhG++mfNok0CE90YbBWtvmDapt 1+PDyjctGfSM+aEdm0UHsk0+5Y4x8/fmk7U3gLmeHF2dDZxjSuyB9rRU08ffhDRFFq L0g3QyQgf1CI7ebN2SQRzXekGr8bql37lsHfXBClsET/LKFAB0Ddwbh2DmQDrwS6hG ZX0MqdVK252vg== From: Saeed Mahameed To: "David S. Miller" , Jakub Kicinski Cc: netdev@vger.kernel.org, Paul Blakey , Oz Shlomo , Eli Cohen , Roi Dayan , Saeed Mahameed Subject: [net 07/11] net/mlx5e: Fix matching on modified inner ip_ecn bits Date: Thu, 6 Jan 2022 16:58:27 -0800 Message-Id: <20220107005831.78909-8-saeed@kernel.org> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20220107005831.78909-1-saeed@kernel.org> References: <20220107005831.78909-1-saeed@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Paul Blakey Tunnel device follows RFC 6040, and during decapsulation inner ip_ecn might change depending on inner and outer ip_ecn as follows: +---------+----------------------------------------+ |Arriving | Arriving Outer Header | | Inner +---------+---------+---------+----------+ | Header | Not-ECT | ECT(0) | ECT(1) | CE | +---------+---------+---------+---------+----------+ | Not-ECT | Not-ECT | Not-ECT | Not-ECT | | | ECT(0) | ECT(0) | ECT(0) | ECT(1) | CE* | | ECT(1) | ECT(1) | ECT(1) | ECT(1)* | CE* | | CE | CE | CE | CE | CE | +---------+---------+---------+---------+----------+ Cells marked above are changed from original inner packet ip_ecn value. Tc then matches on the modified inner ip_ecn, but hw offload which matches the inner ip_ecn value before decap, will fail. Fix that by mapping all the cases of outer and inner ip_ecn matching, and only supporting cases where we know inner wouldn't be changed by decap, or in the outer ip_ecn=CE case, inner ip_ecn didn't matter. Fixes: bcef735c59f2 ("net/mlx5e: Offload TC matching on tos/ttl for ip tunnels") Signed-off-by: Paul Blakey Reviewed-by: Oz Shlomo Reviewed-by: Eli Cohen Reviewed-by: Roi Dayan Signed-off-by: Saeed Mahameed --- .../net/ethernet/mellanox/mlx5/core/en_tc.c | 120 +++++++++++++++++- 1 file changed, 116 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 5e454a14428f..9b3adaccc9be 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c @@ -1949,6 +1949,111 @@ u8 mlx5e_tc_get_ip_version(struct mlx5_flow_spec *spec, bool outer) return ip_version; } +/* Tunnel device follows RFC 6040, see include/net/inet_ecn.h. + * And changes inner ip_ecn depending on inner and outer ip_ecn as follows: + * +---------+----------------------------------------+ + * |Arriving | Arriving Outer Header | + * | Inner +---------+---------+---------+----------+ + * | Header | Not-ECT | ECT(0) | ECT(1) | CE | + * +---------+---------+---------+---------+----------+ + * | Not-ECT | Not-ECT | Not-ECT | Not-ECT | | + * | ECT(0) | ECT(0) | ECT(0) | ECT(1) | CE* | + * | ECT(1) | ECT(1) | ECT(1) | ECT(1)* | CE* | + * | CE | CE | CE | CE | CE | + * +---------+---------+---------+---------+----------+ + * + * Tc matches on inner after decapsulation on tunnel device, but hw offload matches + * the inner ip_ecn value before hardware decap action. + * + * Cells marked are changed from original inner packet ip_ecn value during decap, and + * so matching those values on inner ip_ecn before decap will fail. + * + * The following helper allows offload when inner ip_ecn won't be changed by outer ip_ecn, + * except for the outer ip_ecn = CE, where in all cases inner ip_ecn will be changed to CE, + * and such we can drop the inner ip_ecn=CE match. + */ + +static int mlx5e_tc_verify_tunnel_ecn(struct mlx5e_priv *priv, + struct flow_cls_offload *f, + bool *match_inner_ecn) +{ + u8 outer_ecn_mask = 0, outer_ecn_key = 0, inner_ecn_mask = 0, inner_ecn_key = 0; + struct flow_rule *rule = flow_cls_offload_flow_rule(f); + struct netlink_ext_ack *extack = f->common.extack; + struct flow_match_ip match; + + *match_inner_ecn = true; + + if (flow_rule_match_key(rule, FLOW_DISSECTOR_KEY_ENC_IP)) { + flow_rule_match_enc_ip(rule, &match); + outer_ecn_key = match.key->tos & INET_ECN_MASK; + outer_ecn_mask = match.mask->tos & INET_ECN_MASK; + } + + if (flow_rule_match_key(rule, FLOW_DISSECTOR_KEY_IP)) { + flow_rule_match_ip(rule, &match); + inner_ecn_key = match.key->tos & INET_ECN_MASK; + inner_ecn_mask = match.mask->tos & INET_ECN_MASK; + } + + if (outer_ecn_mask != 0 && outer_ecn_mask != INET_ECN_MASK) { + NL_SET_ERR_MSG_MOD(extack, "Partial match on enc_tos ecn bits isn't supported"); + netdev_warn(priv->netdev, "Partial match on enc_tos ecn bits isn't supported"); + return -EOPNOTSUPP; + } + + if (!outer_ecn_mask) { + if (!inner_ecn_mask) + return 0; + + NL_SET_ERR_MSG_MOD(extack, + "Matching on tos ecn bits without also matching enc_tos ecn bits isn't supported"); + netdev_warn(priv->netdev, + "Matching on tos ecn bits without also matching enc_tos ecn bits isn't supported"); + return -EOPNOTSUPP; + } + + if (inner_ecn_mask && inner_ecn_mask != INET_ECN_MASK) { + NL_SET_ERR_MSG_MOD(extack, + "Partial match on tos ecn bits with match on enc_tos ecn bits isn't supported"); + netdev_warn(priv->netdev, + "Partial match on tos ecn bits with match on enc_tos ecn bits isn't supported"); + return -EOPNOTSUPP; + } + + if (!inner_ecn_mask) + return 0; + + /* Both inner and outer have full mask on ecn */ + + if (outer_ecn_key == INET_ECN_ECT_1) { + /* inner ecn might change by DECAP action */ + + NL_SET_ERR_MSG_MOD(extack, "Match on enc_tos ecn = ECT(1) isn't supported"); + netdev_warn(priv->netdev, "Match on enc_tos ecn = ECT(1) isn't supported"); + return -EOPNOTSUPP; + } + + if (outer_ecn_key != INET_ECN_CE) + return 0; + + if (inner_ecn_key != INET_ECN_CE) { + /* Can't happen in software, as packet ecn will be changed to CE after decap */ + NL_SET_ERR_MSG_MOD(extack, + "Match on tos enc_tos ecn = CE while match on tos ecn != CE isn't supported"); + netdev_warn(priv->netdev, + "Match on tos enc_tos ecn = CE while match on tos ecn != CE isn't supported"); + return -EOPNOTSUPP; + } + + /* outer ecn = CE, inner ecn = CE, as decap will change inner ecn to CE in anycase, + * drop match on inner ecn + */ + *match_inner_ecn = false; + + return 0; +} + static int parse_tunnel_attr(struct mlx5e_priv *priv, struct mlx5e_tc_flow *flow, struct mlx5_flow_spec *spec, @@ -2144,6 +2249,7 @@ static int __parse_cls_flower(struct mlx5e_priv *priv, struct flow_rule *rule = flow_cls_offload_flow_rule(f); struct flow_dissector *dissector = rule->match.dissector; enum fs_flow_table_type fs_type; + bool match_inner_ecn = true; u16 addr_type = 0; u8 ip_proto = 0; u8 *match_level; @@ -2197,6 +2303,10 @@ static int __parse_cls_flower(struct mlx5e_priv *priv, headers_c = get_match_inner_headers_criteria(spec); headers_v = get_match_inner_headers_value(spec); } + + err = mlx5e_tc_verify_tunnel_ecn(priv, f, &match_inner_ecn); + if (err) + return err; } err = mlx5e_flower_parse_meta(filter_dev, f); @@ -2420,10 +2530,12 @@ static int __parse_cls_flower(struct mlx5e_priv *priv, struct flow_match_ip match; flow_rule_match_ip(rule, &match); - MLX5_SET(fte_match_set_lyr_2_4, headers_c, ip_ecn, - match.mask->tos & 0x3); - MLX5_SET(fte_match_set_lyr_2_4, headers_v, ip_ecn, - match.key->tos & 0x3); + if (match_inner_ecn) { + MLX5_SET(fte_match_set_lyr_2_4, headers_c, ip_ecn, + match.mask->tos & 0x3); + MLX5_SET(fte_match_set_lyr_2_4, headers_v, ip_ecn, + match.key->tos & 0x3); + } MLX5_SET(fte_match_set_lyr_2_4, headers_c, ip_dscp, match.mask->tos >> 2); -- 2.33.1