On Wed, Aug 01, Josef Sipek wrote: > This brings up an very interesting (but painful) question...which makes more > sense? Allowing the modifications in only the top-most branch, or any branch > (given the user allows it at mount-time)? My implementation is keeping things simple because of reason. There have been many attempts to get unioning working on the filesystem layer. Most of them failed because of complexity. E.g. BSD throwed away all of the filesystem stacking support after they tried to fix unionfs for years. Writing to lower layers is making things unnecessary complex. Therefore I left it out. > > > 1) "cp -r" the entire subtree being renamed to highest-priority branch, and > > > rename there (you might have to recreate a series of directories to have a > > > place to "cp" to...so you got "cp -r" _AND_ "mkdir -p"-like code in the VFS! > > > 1/2 a :) ) > > > > I think this is the only alternative, given the design. > > Right. Doing something like this at the filesystem level (as we do in > unionfs) seems less painful - filesystems are places full of all sorts of > nefarious activities to begin with. Having it in the VFS seems...even > uglier. The userspace is doing it since I return -EXDEV. And that even comes for free. I don't need to hack around and call back into VFS as you do. It is so simple and straightforward in the VFS. - 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
