From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=waldekranz-com.20210112.gappssmtp.com; s=20210112; h=from:to:cc:subject:in-reply-to:references:date:message-id :mime-version; bh=Y0ggJ9V38cE1b6AbUVeGyXnI9Fgl1hR/3Vx8sEEmZeo=; b=kCnKg4MIsOoya9TXhoPOk1grh79P74LsBE9ARzsWX9dqD6Xc4MwHcG/q+gXUdM5q8c lu4ocMfkObZK/AaB08efYQuvWYSm4f1Hpe+y+HI15FrLQV6qRBuK3daxp6giD9z74GQz fTm7w3TV+MehDK8HZwZziLrrgkqPd0Tic8iC+9cAy9It5hvPlIdY28Zu8UUvETekYoEu 6Q8fbtrAwGWTMpV+MHDSUPHzPeM3rR1lNhG8qnn1toEzvxO8w+rb0PiKbYxlA8AB6ZxZ pBK3+4rthtEjx2XQmQnCFY1F4HAVLMjADxKIa2p1TLoqdBtqpUUMoqJ9BGonXYaw/Pmq BIiw== From: Tobias Waldekranz In-Reply-To: <20220315171108.ameddbqv2sehq3pp@skbuf> References: <20220315002543.190587-1-tobias@waldekranz.com> <20220315002543.190587-11-tobias@waldekranz.com> <20220315171108.ameddbqv2sehq3pp@skbuf> Date: Wed, 16 Mar 2022 10:15:18 +0100 Message-ID: <8735jil0m1.fsf@waldekranz.com> MIME-Version: 1.0 Content-Type: text/plain Subject: Re: [Bridge] [PATCH v4 net-next 10/15] net: dsa: Validate hardware support for MST List-Id: Linux Ethernet Bridging List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Vladimir Oltean Cc: Ivan Vecera , Andrew Lunn , Florian Fainelli , Jiri Pirko , Petr Machata , Nikolay Aleksandrov , bridge@lists.linux-foundation.org, Russell King , Vivien Didelot , Ido Schimmel , netdev@vger.kernel.org, Cooper Lees , Roopa Prabhu , kuba@kernel.org, Matt Johnston , davem@davemloft.net, linux-kernel@vger.kernel.org On Tue, Mar 15, 2022 at 19:11, Vladimir Oltean wrote: > On Tue, Mar 15, 2022 at 01:25:38AM +0100, Tobias Waldekranz wrote: >> When joining a bridge where MST is enabled, we validate that the >> proper offloading support is in place, otherwise we fallback to >> software bridging. >> >> When then mode is changed on a bridge in which we are members, we >> refuse the change if offloading is not supported. >> >> At the moment we only check for configurable learning, but this will >> be further restricted as we support more MST related switchdev events. >> >> Signed-off-by: Tobias Waldekranz >> --- >> net/dsa/dsa_priv.h | 2 ++ >> net/dsa/port.c | 22 ++++++++++++++++++++++ >> net/dsa/slave.c | 6 ++++++ >> 3 files changed, 30 insertions(+) >> >> diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h >> index f20bdd8ea0a8..2aba420696ef 100644 >> --- a/net/dsa/dsa_priv.h >> +++ b/net/dsa/dsa_priv.h >> @@ -234,6 +234,8 @@ int dsa_port_vlan_filtering(struct dsa_port *dp, bool vlan_filtering, >> struct netlink_ext_ack *extack); >> bool dsa_port_skip_vlan_configuration(struct dsa_port *dp); >> int dsa_port_ageing_time(struct dsa_port *dp, clock_t ageing_clock); >> +int dsa_port_mst_enable(struct dsa_port *dp, bool on, >> + struct netlink_ext_ack *extack); >> int dsa_port_mtu_change(struct dsa_port *dp, int new_mtu, >> bool targeted_match); >> int dsa_port_fdb_add(struct dsa_port *dp, const unsigned char *addr, >> diff --git a/net/dsa/port.c b/net/dsa/port.c >> index 58291df14cdb..02214033cec0 100644 >> --- a/net/dsa/port.c >> +++ b/net/dsa/port.c >> @@ -321,6 +321,11 @@ static void dsa_port_bridge_destroy(struct dsa_port *dp, >> kfree(bridge); >> } >> >> +static bool dsa_port_supports_mst(struct dsa_port *dp) >> +{ >> + return dsa_port_can_configure_learning(dp); >> +} >> + >> int dsa_port_bridge_join(struct dsa_port *dp, struct net_device *br, >> struct netlink_ext_ack *extack) >> { >> @@ -334,6 +339,9 @@ int dsa_port_bridge_join(struct dsa_port *dp, struct net_device *br, >> struct net_device *brport_dev; >> int err; >> >> + if (br_mst_enabled(br) && !dsa_port_supports_mst(dp)) >> + return -EOPNOTSUPP; >> + >> /* Here the interface is already bridged. Reflect the current >> * configuration so that drivers can program their chips accordingly. >> */ >> @@ -735,6 +743,20 @@ int dsa_port_ageing_time(struct dsa_port *dp, clock_t ageing_clock) >> return 0; >> } >> >> +int dsa_port_mst_enable(struct dsa_port *dp, bool on, >> + struct netlink_ext_ack *extack) >> +{ >> + if (!on) >> + return 0; >> + >> + if (!dsa_port_supports_mst(dp)) { >> + NL_SET_ERR_MSG_MOD(extack, "Hardware does not support MST"); >> + return -EINVAL; >> + } >> + >> + return 0; >> +} > > Experimenting a bit... maybe this looks tidier? We make the "if" condition > have the same basic structure as the previous "if (br_mst_enabled(br) && > !dsa_port_supports_mst(dp))", albeit transformed using De Morgan's rules. > > { > if (!on || dsa_port_supports_mst(dp)) > return 0; > > NL_SET_ERR_MSG_MOD(extack, "Hardware does not support MST"); > return -EINVAL; > } I initially had it like this. It looks tidier, yes - but to me the intent is less obvious when reading it. How about: { if (on && !dsa_port_supports_mst(dp)) { NL_SET_ERR_MSG_MOD(extack, "Hardware does not support MST"); return -EINVAL; } return 0; } >> + >> int dsa_port_pre_bridge_flags(const struct dsa_port *dp, >> struct switchdev_brport_flags flags, >> struct netlink_ext_ack *extack) >> diff --git a/net/dsa/slave.c b/net/dsa/slave.c >> index 647adee97f7f..879d18cc99cb 100644 >> --- a/net/dsa/slave.c >> +++ b/net/dsa/slave.c >> @@ -463,6 +463,12 @@ static int dsa_slave_port_attr_set(struct net_device *dev, const void *ctx, >> >> ret = dsa_port_ageing_time(dp, attr->u.ageing_time); >> break; >> + case SWITCHDEV_ATTR_ID_BRIDGE_MST: >> + if (!dsa_port_offloads_bridge_dev(dp, attr->orig_dev)) >> + return -EOPNOTSUPP; >> + >> + ret = dsa_port_mst_enable(dp, attr->u.mst, extack); >> + break; >> case SWITCHDEV_ATTR_ID_PORT_PRE_BRIDGE_FLAGS: >> if (!dsa_port_offloads_bridge_port(dp, attr->orig_dev)) >> return -EOPNOTSUPP; >> -- >> 2.25.1 >>