From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 571592563 for ; Sat, 9 Dec 2023 17:02:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="DB/SMpLN" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6E851C433C7; Sat, 9 Dec 2023 17:02:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1702141368; bh=nRJiA/c/xx7fFzg+0MvluRUxFBY1g4LX9RtAoR1rb7o=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=DB/SMpLN3+TSmIJTzyBHUsFWgUxwjdSaEWhrwKajdPhTmjj29bhCaUo+Zw8tMAcBU r738kfP9NIslgrbcsmvxqIQCp9Ml+JACSPnN8T+2l7A3Up0BZmxk537Qkh4YRjvhKk W1T+uHnXLv14X7u5PyCRIPjh42BzD+/jddjwXIP5//E8eCtDTpoGWoQOynniJhRtvw U9BRNCgB/3WIGqoH7yF+urooe72ZwdZTc4Z12dp6XKjRTMqNL/yOi59W2Eg1TKzDzY GxWZhJgE/2admwfwdhjDYOXEm3UNFjhz6sMSypzc9EZvAK+t8OTlYIJl5FoS73S/9y VKQxpiTGaMOnw== Date: Sat, 9 Dec 2023 17:02:41 +0000 From: Simon Horman To: Maxime Chevallier Cc: davem@davemloft.net, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, thomas.petazzoni@bootlin.com, Andrew Lunn , Jakub Kicinski , Eric Dumazet , Paolo Abeni , Russell King , linux-arm-kernel@lists.infradead.org, Christophe Leroy , Herve Codina , Florian Fainelli , Heiner Kallweit , Vladimir Oltean , =?utf-8?B?S8O2cnk=?= Maincent , Jesse Brandeburg , Jonathan Corbet , Marek =?utf-8?B?QmVow7pu?= , Piergiorgio Beruto , Oleksij Rempel , =?utf-8?Q?Nicol=C3=B2?= Veronese Subject: Re: [RFC PATCH net-next v3 01/13] net: phy: Introduce ethernet link topology representation Message-ID: <20231209170241.GA5817@kernel.org> References: <20231201163704.1306431-1-maxime.chevallier@bootlin.com> <20231201163704.1306431-2-maxime.chevallier@bootlin.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20231201163704.1306431-2-maxime.chevallier@bootlin.com> On Fri, Dec 01, 2023 at 05:36:51PM +0100, Maxime Chevallier wrote: > Link topologies containing multiple network PHYs attached to the same > net_device can be found when using a PHY as a media converter for use > with an SFP connector, on which an SFP transceiver containing a PHY can > be used. > > With the current model, the transceiver's PHY can't be used for > operations such as cable testing, timestamping, macsec offload, etc. > > The reason being that most of the logic for these configuration, coming > from either ethtool netlink or ioctls tend to use netdev->phydev, which > in multi-phy systems will reference the PHY closest to the MAC. > > Introduce a numbering scheme allowing to enumerate PHY devices that > belong to any netdev, which can in turn allow userspace to take more > precise decisions with regard to each PHY's configuration. > > The numbering is maintained per-netdev, in a phy_device_list. > The numbering works similarly to a netdevice's ifindex, with > identifiers that are only recycled once INT_MAX has been reached. > > This prevents races that could occur between PHY listing and SFP > transceiver removal/insertion. > > The identifiers are assigned at phy_attach time, as the numbering > depends on the netdevice the phy is attached to. > > Signed-off-by: Maxime Chevallier Hi Maxime, some minor feedback from my side. ... > diff --git a/drivers/net/phy/Makefile b/drivers/net/phy/Makefile > index f65e85c91fc1..3cf7774df57e 100644 > --- a/drivers/net/phy/Makefile > +++ b/drivers/net/phy/Makefile > @@ -2,7 +2,7 @@ > # Makefile for Linux PHY drivers > > libphy-y := phy.o phy-c45.o phy-core.o phy_device.o \ > - linkmode.o > + linkmode.o phy_link_topology.o > mdio-bus-y += mdio_bus.o mdio_device.o > > ifdef CONFIG_MDIO_DEVICE > diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c ... > @@ -265,6 +266,14 @@ static void phy_mdio_device_remove(struct mdio_device *mdiodev) > > static struct phy_driver genphy_driver; > > +static struct phy_link_topology *phy_get_link_topology(struct phy_device *phydev) > +{ > + if (phydev->attached_dev) > + return &phydev->attached_dev->link_topo; > + > + return NULL; > +} > + This function is declared static but is unused, which causes allmodconfig W=1 builds to fail. Perhaps it could be introduced in a latter patch where it is used? ... > diff --git a/drivers/net/phy/phy_link_topology.c b/drivers/net/phy/phy_link_topology.c ... > +void phy_link_topo_init(struct phy_link_topology *topo) > +{ > + xa_init_flags(&topo->phys, XA_FLAGS_ALLOC1); > + topo->next_phy_index = 1; > +} ... > diff --git a/include/linux/phy_link_topology.h b/include/linux/phy_link_topology.h ... > +#else > +static struct phy_device *phy_link_topo_get_phy(struct phy_link_topology *topo, > + u32 phyindex) > +{ > + return NULL; > +} > + > +static int phy_link_topo_add_phy(struct phy_link_topology *topo, > + struct phy_device *phy, > + enum phy_upstream upt, void *upstream) > +{ > + return 0; > +} > + > +static void phy_link_topo_del_phy(struct phy_link_topology *topo, > + struct phy_device *phy) > +{ > +} > +#endif nit: functions in .h should be declared static inline ... > diff --git a/net/core/dev.c b/net/core/dev.c ... > @@ -10832,6 +10833,8 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, > #ifdef CONFIG_NET_SCHED > hash_init(dev->qdisc_hash); > #endif > + phy_link_topo_init(&dev->link_topo); > + I don't think this can work unless PHYLIB is compiled as a built-in. > dev->priv_flags = IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM; > setup(dev); > > -- > 2.42.0 >