On Mon, Jan 08, 2007 at 02:02:24PM -0800, Andrew Morton wrote: > On Mon, 08 Jan 2007 16:30:48 -0500 > Shaya Potter <spotter@xxxxxxxxxxxxxxx> wrote: > > > On Mon, 2007-01-08 at 13:19 -0800, Andrew Morton wrote: > > > On Mon, 8 Jan 2007 14:43:39 -0500 (EST) Shaya Potter <spotter@xxxxxxxxxxxxxxx> wrote: > > > > 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. > > > > the difference is bind mounts are a vfs construct, while unionfs is a > > file system. > > Well yes. So the top-level question is "is this the correct way of doing > unionisation?". Namespace unification doesn't seem to fit into neither vfs-only nor fs-only category. My guess is that some of the code that's currently in unionfs could be replaced by some vfs-level magic. > I suspect not, in which case unionfs is at best a stopgap until someone > comes along and implements unionisation at the VFS level, at which time > unionfs goes away. > > That could take a long time. The questions we're left to ponder over are > things like > > a) is unionfs a sufficiently useful stopgap to justify a merge and We (unionfs team) think so :) > b) would an interim merge of unionfs increase or decrease the motivation > for someone to do a VFS implementation? And is a VFS implementation the right way to do it? > I suspect the answer to b) is "increase": if unionfs proves to be useful > then people will be motivated to produce more robust implementations of the > same functionality. I think it would "increase" the chance of people doing the right thing - whatever it may be. > Is there vendor interest in unionfs? Many people are currently using the full - lkml-unsafe :) version of the code which has a considerable amount of bells and whistles - at least compared to the minimal version submitted. I want to take the good things "port" them over and make sure everything is good. Josef "Jeff" Sipek. -- The box said "Windows XP or better required". So I installed Linux. - To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
