On 12 May 2000, Eric W. Biederman wrote:
> Could someone tell me in small words why we think there is a guarantee of
> uniqueness for entries in directories. I admit that on a stable directory
> that is not modified this is true. However if anyone is touching the
> directory while you are reading it, the guarantee of uniqueness breaks down.
Yeah, but you rarely get "." twice...
> Which at least scales to millions of entries if not to thousands of directories
> mounted on top of each other.
Stop here. We don't mount them on top of each other - they all go into the
list which sits atop of the mountpoint. And mountpoint may be an element of
that list - that's it. That way we can add them both to beginning and to
end.
> Seeing if we can avoid deduping the list for userspace or simply exporting the
>problem
> to user space as a user space fs, sounds like a more reasonable solution.
I'ld rather live without the need of userspace filesystems at that place - it
should be usable for /dev, damnit.