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Date:   Sat, 28 Nov 2020 16:54:50 -0600
From:   "Serge E. Hallyn" <serge@hallyn.com>
To:     Christian Brauner <christian.brauner@ubuntu.com>
Cc:     Alexander Viro <viro@zeniv.linux.org.uk>,
        Christoph Hellwig <hch@infradead.org>,
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Subject: Re: [PATCH v3 00/38] idmapped mounts
Message-ID: <20201128225450.GC22812@mail.hallyn.com>
References: <20201128213527.2669807-1-christian.brauner@ubuntu.com>
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On Sat, Nov 28, 2020 at 10:34:49PM +0100, Christian Brauner wrote:
> Hey everyone,

Hey Christian,

a general request.  Argue with me if it seems misguided.

When looking at a patch or a small hunk of code, these days, if a variable
called 'ns' or 'user_ns' is seen passed to a function, it can be easy to
assume which user_ns it is based on what you think would make sense, but if
your assumption is wrong, your patch review will be wrong.

Can we stick to a convention where we have maybe

subj_userns - the userns of the task seeking some action
obj_userns - the userns of the thing being acted on - task, superblock,...
mnt_userns - the userns of a mountpoint through which an object is seen

You're replacing a lot of such callers and callsites in this patchset, so
this would be a great time to start doing that.

-serge