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Date:   Tue, 1 Dec 2020 11:18:06 +0100
From:   Christian Brauner <christian.brauner@ubuntu.com>
To:     "Serge E. Hallyn" <serge@hallyn.com>
Cc:     Alexander Viro <viro@zeniv.linux.org.uk>,
        Christoph Hellwig <hch@infradead.org>,
        linux-fsdevel@vger.kernel.org,
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        OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>,
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Subject: Re: [PATCH v3 00/38] idmapped mounts
Message-ID: <20201201101806.3gd4kj36kpg4dif3@wittgenstein>
References: <20201128213527.2669807-1-christian.brauner@ubuntu.com>
 <20201128225450.GC22812@mail.hallyn.com>
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On Sat, Nov 28, 2020 at 04:54:50PM -0600, Serge Hallyn wrote:
> 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.

Hey Serge,

this makes a lot of sense. I'll convert all accesses to the vfsmount's
userns we're introducing in this series to to mnt_userns at least.

Christian