Re: knfsd and FS_REQUIRES_DEV

Linus Torvalds (torvalds@transmeta.com)
Wed, 12 Dec 2001 00:46:10 +0000 (UTC)


In article <20011211.162011.21927662.davem@redhat.com>,
David S. Miller <davem@redhat.com> wrote:
> From: Elliot Lee <sopwith@redhat.com>
> Date: Tue, 11 Dec 2001 19:13:48 -0500 (EST)
>
> I'm looking for information on knfsd's requirement that a filesystem be
> FS_REQUIRES_DEV in order to export it. Would someone point me in the right
> direction?
>
> Needing to implement some not-quite-kosher exports,
>
>NFSD puts dev/ino into the filehandles it gives to the
>client, it uses this to lookup the inode in question.

Well, that actually could work with things like /proc, which actually
has meaningful inode numbers. They may not be stable across reboots, of
course, nor even really stable in general, but in _theory_ there's
nothing to keep us from exporting /proc files and potentially other
virtual filesystems.

In practice I suspect there are tons of other problems, not the least of
which is that /proc doesn't give a proper filesize.

Other not-so-kosher filesystems (ie tmpfs) might be easier than /proc in
those respects.

Linus
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/