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Date:   Fri, 29 Mar 2019 07:51:07 +0100
From:   Marek Behun <marek.behun@nic.cz>
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     Tejun Heo <tj@kernel.org>, linux-kernel@vger.kernel.org,
        Pavel Machek <pavel@ucw.cz>,
        Jacek Anaszewski <jacek.anaszewski@gmail.com>
Subject: Re: kernfs: can read/write method grow buffer size?
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References: <20190329040922.34ab01c6@nic.cz>
        <20190329062253.GA9659@kroah.com>
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> If this is just for kernfs, and you have your own filesystem, sure, we
> can probably do something here.  But if this is for sysfs, no, you all
> need to keep to the "one value per file" rule that we have there
> please.

Greg, the file satisfies the "one value per file" rule. That value is
the currently selected trigger. Writing a trigger name changes this
value. It is just that reading also prints all the supported triggers.