Re: [PATCH][RFC] NFS: Propagate 'fsc' mount option through automounts

[David Howells <dhowells@redhat.com>]

Trond Myklebust <Trond.Myklebust@netapp.com> wrote:

> > > Why not just use the mount path as the default uniquifier?

In fact, why change it from being blank?  If I do this:

	The natural thing would be to use the mount path that is required to
	locate the super block's root dentry on the server (i.e. the mount
	path for sb->s_root).

then it may as well be blank, since the FSID is a sufficient uniquifier, and
that's also included in the key.


Where a uniquifier is needed is when someone sets up two mounts of the same
thing, but with different network parameters as these aren't recorded in the
key.  Under such a circumstance, manual intervention is required in the form
of a supplied uniquifier on one of the mounts.

That uniquifier should also only apply to the superblock actually being
mounted, I think; but it's probably okay to apply it to all the intervening
transient superblocks from root that nfs_follow_remote_path() causes to exist,
and just accept that you might get a little bit of rubbish in the cache once
we start caching directories.

Also, the uniquifier would be applied to all superblocks that get created by
automounts under a superblock that has a uniquifier.

David