Re: FUSE merging?

[Miklos Szeredi <miklos@szeredi.hu>]

> > There's
> > nothing magic about that.  It's as if it was N different servers for N
> > different clients, only more effective.
> 
> Not entirely, there is a UID dependancy.

Ahh, so there is.

Does it actually work?  I doubt it.  The VFS won't allow two different
dentries to refer to the same name.  And without that, how would you
have several inodes for a single name?

> > I think what you call namespace invariance is basically true for all
> > existing filesystems.  There could be a filesystem which returns
> > different directory contents based on whatever it wants, but it can't
> > return a different "dentry" for the same name.
> 
> This is not what I mean. The directory contents itself must be identical
> for every user. And every name must of course correspond with only one
> dentry. That's name-space invariance IMO.

OK.

> > > IMHO The namespace argument against FUSE is weak for multiple
> > > reasons. The only variancy I see is when crossing the mount
> > > point. And that disappears once EACCES is returned when
> > > non-ptraceable processes try to cross it.
> > 
> > Yes, but still this is just a difference in permission, and not a
> > difference in namespace.
> 
> Exactly. And such a difference in permission already exists for (sane)
> networked file systems such as NFS with "squash_root" in effect on
> the server.

Agreed.

Miklos
-
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/