sparc 32-bit dirent broken

[David Miller]

From: David Miller <davem@davemloft.net>
Date: Thu, 10 Oct 2013 16:43:08 -0400 (EDT)

> From: Florian Weimer <fweimer@redhat.com>
> Date: Thu, 10 Oct 2013 21:48:05 +0200
> 
>> On 10/10/2013 09:36 PM, David Miller wrote:
>> 
>>> That didn't fix things, attached is the strace log with "-v" for a
>>> posix/tst-dir run.
>> 
>> Hmm.  strace is decoding the kernel buffers, too, so it's not
>> particularly helpful.  I'd rather see the raw bytes in this case.
>> 
>> I'll try to reproduce this on ppc32 (but I did test things there).
> 
> Meanwhile I'll try to add some stderr tracing to readdir_r.c and
> see if I can get anything useful out of it during the test.

The very first call to getdents goes like this:

readdir_r: dirp->offset[0] dirp->size[0]
readdir_r: __GETDENTS() maxread[32768] bytes[-1] errno[14]

errno 14 is -EFAULT on sparc.

I suspect the alignof needs to be adjusted in struct __dirstream so
that data[] is 64-bit aligned on platforms that need that.

I'll test out this theory.