Re: HSM (was Re: [malware-list] TALPA - a threat model? wellsorta.)

From: Rik van Riel
Date: Tue Aug 19 2008 - 12:23:50 EST


On Tue, 19 Aug 2008 09:14:16 +0200
Pavel Machek <pavel@xxxxxxx> wrote:

> On Mon 2008-08-18 12:43:39, Rik van Riel wrote:
> > On Mon, 18 Aug 2008 16:33:13 +0100
> > Alan Cox <alan@xxxxxxxxxxxxxxxxxxx> wrote:
> >
> > > > I could probably buy that, but I don't know how an HSM would
> > > > work. Would we have everything we need at open for them to fire
> > > > off?
> > > >
> > > > /me is HSM clueless and trying to include their needs is
> > > > proving a challenge.
> > >
> > > So don't bother. Its a theoretical use for the most part so we can
> > > mangle the interface later.
> >
> > Think of a consumer HSM application: backup to rsync.net
> > or Amazon S3.
> >
> > Instead of waiting for the whole backup to be restored,
> > you can start using the filesystem immediately. The
> > block-on-open hook can be used by the restore program
> > to fetch files from the remote backup site on an
> > as-needed basis, with a full restore going on in the
> > background.
> >
> > If the block-on-open hook can be used for that (even
> > with additional magic, like creating empty HSM inodes
> > with a special attr to notify "the data lives elsewhere"),
> > HSM should be good.
> >
> > The "data lives elsewhere" bit/xattr/whatever could also
> > be used on directories, so not even the whole directory
> > tree would have to be restored right on restore :)
>
> But is this really needed to be cross-filesystem thing? I'd expect
> this to be implemented with FUSE, maybe FUSE+unionfs...

If you think FUSE+unionfs is a cleaner solution than one
hook in the VFS, I've got a bridge to sell you.

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