Re: reiser4 plugins

David Masover
2005-07-05T22:23:47Z

Hans Reiser wrote:
> Hubert Chan wrote:
>
>
>>On Fri, 01 Jul 2005 03:06:19 -0500, David Masover <ninja@slaphack.com> said:
>>
>>
>>
>>
>>>Hubert Chan wrote:
>>>
>>>
>>
>>
>>
>>
>>>>The main thing blocking file-as-dir is that there are some
>>>>locking(IIRC?) issues. And, of course, some people wouldn't want it
>>>>to be merged into the mainline kernel. (Of course, the latter
>>>>doesn't prevent Namesys from maintaining their own patches for people
>>>>to play around with.)
>>>>
>>>>
>>
>>
>>
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>>>What's the locking issue? I think that was more about transactions...
>>>
>>>
>>
>>It was whatever was Al Viro's (technical) complaint about file-as-dir.
>>I don't remember exactly what it was. The technical people know what it
>>is (and the Namesys guys are probably working on it), and the exact
>>issue doesn't concern us non-technical people that much, so I don't feel
>>like looking it up. But if you want to, just look for Al Viro's message
>>in this thread.
>>
>>
>>
>
> Cycle detection when hard links to directories are allowed. There is a
> debate over whether cycle detection is feasible that can only be
> resolved by working code or a formal proof that it is not
> computationally feasible.

Ah. But then, one solution was to avoid the issue at all, and have the
directory inside a file act as a mountpoint. After all, mount --bind
doesn't cause problems...

Hey! This sounds like metafs (/meta) already! I wonder if we can do
file-as-dir in /meta, and just not support user-created hardlinks there?
(other than creating brand-new files, of course...)