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From:   Arnd Bergmann <arnd@arndb.de>
Date:   Thu, 10 Jan 2019 23:42:32 +0100
Message-ID: <CAK8P3a2f4SCJXrm6HWO9UKY-akSW+ONNpOvQOtYbia_fRo9ciQ@mail.gmail.com>
Subject: Re: [PATCH 00/15] arch: synchronize syscall tables in preparation for y2038
To:     Joseph Myers <joseph@codesourcery.com>
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On Thu, Jan 10, 2019 at 7:10 PM Joseph Myers <joseph@codesourcery.com> wrote:
>
> On Thu, 10 Jan 2019, Arnd Bergmann wrote:
>
> > - Add system calls that have not yet been integrated into all
> >   architectures but that we definitely want there.
>
> glibc has a note that alpha lacks statfs64, any plans for that?

Good catch, I missed that because all other 64-bit architectures
have a statfs() call with 64-bit fields. I see that it also has an
osf_statfs64 structure and system call with lots of padding and some
oddly sized fields: f_type, f_flags and f_namemax are only 16 bits
wide, the rest is all 64-bit.

Adding the regular statfs64() should be easy enough, we just need to
decide which layout to use:

a) use the currently unused 'struct statfs64' as provided by the
    alpha uapi headers, which has a 32-bit __statfs_word but
    64-bit f_blocks, f_bfree, f_bavail, f_files, and f_ffree.

b) copy asm-generic/statfs.h to the alpha asm/statfs.h and
    change statfs64 to have the regular layout that we use
    on all other 64-bit architectures, using all 64-bit fields.

The other open question for alpha (as mentioned in one of the
patches I sent) would be whether to add get{eg,eu,g,p,pp,u}id()
with the regular calling conventions.

       Arnd