Re: [PATCH 01/24] Unionfs: Documentation

[Josef Sipek]

On Mon, Jan 08, 2007 at 01:19:57PM -0800, Andrew Morton wrote:
... 
> If it's not in the changelog or the documentation, it doesn't exist.

Good point. I'll add it for next time.

> >  It's the same thing as modifying a block 
> > device while a file system is using it.  Now, when unionfs gets confused, 
> > it shouldn't oops, but would one expect ext3 to allow one to modify its 
> > backing store while its using it?
> 
> There's no such problem with bind mounts.  It's surprising to see such a
> restriction with union mounts.

Bind mounts are a purely VFS level construct. Unionfs is, as the name
implies, a filesystem. Last year at OLS, it seemed that a lot of people
agreed that unioning is neither purely a fs construct, nor purely a vfs
construct.

I'm using Unionfs (and ecryptfs) as guinea pigs to make linux fs stacking
friendly - a topic to be discussed at LSF in about a month.

Josef "Jeff" Sipek.

-- 
Computer Science is no more about computers than astronomy is about
telescopes.
		- Edsger Dijkstra
-
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/