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From: Terry Lambert <terry@lambert.org>
Message-Id: <199611062031.NAA08732@phaeton.artisoft.com>
Subject: Re: Davidg bug (was: mount panics & hangs)
To: julian@whistle.com (Julian Elischer)
Date: Wed, 6 Nov 1996 13:31:19 -0700 (MST)
Cc: terry@lambert.org, archie@whistle.com, freebsd-hackers@FreeBSD.org,
        davidg@FreeBSD.org
In-Reply-To: <3280E3BC.15FB7483@whistle.com> from "Julian Elischer" at Nov 6, 96 11:15:08 am
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> If you want I can try work a patch and send it to you
> for comments. (though I don't yet understand why there needs to be
> both vfs_busy and vfs_lock)

Lock for drain (no additional entry is allowed, current users should
exit), lock for object destruction (all current users must have exited).

The idea is that there might be some latent operations that haven't
completed, and you want to let them complete before you do your thing,
but you want to make sure no new operations start after you decide to
do your thing but before you can safely do it.


					Terry Lambert
					terry@lambert.org
---
Any opinions in this posting are my own and not those of my present
or previous employers.