Re: [PATCH 3/6 linux-next] fs/affs: make affs exportable

Fabian Frederick
2017-01-04T05:54:09Z

> On 03 January 2017 at 23:29 Al Viro <viro@ZenIV.linux.org.uk> wrote:
>
>
> On Tue, Jan 03, 2017 at 10:30:39PM +0100, Fabian Frederick wrote:
> > Add standard functions making AFFS work with NFS.
> >
> > Functions based on ext4 implementation.
> > Tested on loop device.
>
> How the hell is that supposed to work with cold dcache?  You don't have
> ->get_parent() there at all...
>
> There *IS* a reference to parent directory in those suckers - not the same
> kind as in normal unix filesystems (".." is not a directory entry there -
> it's all fake), but it's doable.  be32_to_cpu(AFFS_TAIL(sb, bh)->parent)
> would be the inumber you need, where bh is the inode block of directory.
>
> So it can be done, but not in this form.  NAK for the time being...

I worked on that function declared optional in
Documentation/filesystems/nfs/Exporting
but was unable to test it.

Regards,
Fabian