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From:   Dario Binacchi <dario.binacchi@amarulasolutions.com>
Date:   Tue, 26 Jul 2022 14:11:48 +0200
Message-ID: <CABGWkvrknM0VS2V1TAjyjeoE0n2yXGLvv6ucvO-z23nL=EXvXQ@mail.gmail.com>
Subject: Re: [PATCH v2 2/6] can: slcan: remove legacy infrastructure
To:     Marc Kleine-Budde <mkl@pengutronix.de>
Cc:     linux-kernel@vger.kernel.org, michael@amarulasolutions.com,
        Amarula patchwork <linux-amarula@amarulasolutions.com>,
        Jeroen Hofstee <jhofstee@victronenergy.com>,
        Oliver Hartkopp <socketcan@hartkopp.net>,
        Max Staudt <max@enpas.org>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Wolfgang Grandegger <wg@grandegger.com>,
        linux-can@vger.kernel.org, netdev@vger.kernel.org
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On Tue, Jul 26, 2022 at 1:58 PM Marc Kleine-Budde <mkl@pengutronix.de> wrote:
>
> On 26.07.2022 12:11:33, Dario Binacchi wrote:
> > Hello Marc,
> >
> > On Mon, Jul 25, 2022 at 2:38 PM Marc Kleine-Budde <mkl@pengutronix.de> wrote:
> > >
> > > On 25.07.2022 08:54:15, Dario Binacchi wrote:
> > > > Taking inspiration from the drivers/net/can/can327.c driver and at the
> > > > suggestion of its author Max Staudt, I removed legacy stuff like
> > > > `SLCAN_MAGIC' and `slcan_devs' resulting in simplification of the code
> > > > and its maintainability.
> > > >
> > > > The use of slcan_devs is derived from a very old kernel, since slip.c
> > > > is about 30 years old, so today's kernel allows us to remove it.
> > > >
> > > > The .hangup() ldisc function, which only called the ldisc .close(), has
> > > > been removed since the ldisc layer calls .close() in a good place
> > > > anyway.
> > > >
> > > > The old slcanX name has been dropped in order to use the standard canX
> > > > interface naming. It has been assumed that this change does not break
> > > > the user space as the slcan driver provides an ioctl to resolve from tty
> > > > fd to netdev name.
> > >
> > > Is there a man page that documents this iotcl? Please add it and/or the
> > > IOCTL name.
> >
> > I have not found documentation of the SIOCGIFNAME ioctl for the line discipline,
> > but only for netdev (i. e.
> > https://man7.org/linux/man-pages/man7/netdevice.7.html),
>
> Ok - What about:
>
> The old slcanX name has been dropped in order to use the standard canX
> interface naming. The ioctl SIOCGIFNAME can be used to query the name of
> the created interface. Further There are several ways to get stable
> interfaces names in user space, e.g. udev or systemd-networkd.

Good! I will update the commit message in the next version I will submit.
Thanks and regards,

Dario
>
> Marc
>
> --
> Pengutronix e.K.                 | Marc Kleine-Budde           |
> Embedded Linux                   | https://www.pengutronix.de  |
> Vertretung West/Dortmund         | Phone: +49-231-2826-924     |
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-- 

Dario Binacchi

Embedded Linux Developer

dario.binacchi@amarulasolutions.com

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