Re: [RFC][PATCH v3 01/10] fs: common implementation of file type

[Amir Goldstein]

On Wed, Oct 24, 2018 at 4:02 PM Theodore Y. Ts'o <tytso@xxxxxxx> wrote:
>
> 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?
>

IDGI. Why do we want this file in uapi?
The DT_ constants are already defined by glibc dirent.h
and the FT_ constants and macros we don't want to expose
to uapi at all. Right?

Maybe all we need is a comment above DT_ constants
that those are defined by POSIX and in glibc dirent.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),

Very trivial code that has had an out of bounds access bug for two
decades and bug was duplicated to 7 filesystems. IMO, fixing the bug in
one place instead of 7 is a good enough reason for re-factoring.

Thanks,
Amir.