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Date:   Wed, 24 Oct 2018 09:02:06 -0400
From:   "Theodore Y. Ts'o" <tytso@mit.edu>
To:     Phillip Potter <phil@philpotter.co.uk>
Cc:     viro@zeniv.linux.org.uk, linux-kernel@vger.kernel.org,
        amir73il@gmail.com, linux-fsdevel@vger.kernel.org
Subject: Re: [RFC][PATCH v3 01/10] fs: common implementation of file type
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On Tue, Oct 23, 2018 at 09:19:53PM +0100, Phillip Potter wrote:
> diff --git a/include/linux/file_type.h b/include/linux/file_type.h

Shouldn't this be in include/uapi/linux/fs_types.h?

One of things which must be made crystal clear is these definitions
MUST NOT ever change.  It would break the Userspace ABI, and would
break file systems on-disk format.

It might also be useful to be clear *why* we are making this change in
the first place.  Code refactorization is good from a code maintenance
perspective (either to fix bugs, although this code is pretty
trivial), or to make it easier to make changes in a single central
place (which MUST NOT) happen, or to make the compiled code more
compact.

So some documentation of how much text is actually saved might be
worthwhile.

						- Ted