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From: =?utf-8?Q?Dag-Erling_Sm=C3=B8rgrav?= <des@des.no>
To: Alfred Perlstein <alfred@freebsd.org>
References: <20100908180333.GG69795@elvis.mu.org>
Date: Thu, 09 Sep 2010 00:13:19 +0200
In-Reply-To: <20100908180333.GG69795@elvis.mu.org> (Alfred Perlstein's message
	of "Wed, 8 Sep 2010 11:03:33 -0700")
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Cc: fs@freebsd.org
Subject: Re: leverage pseudofs for autofs?
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Alfred Perlstein <alfred@freebsd.org> writes:
> The basic requirements of autofs are:
>
> 1) In-memory filesystem.
> 2) if a lookup is done for a non-existant dir
>    entry then block the process.  (unless it's
>    "special" ie. the actual automounter).
> 3) for readdir, do some magic to send requests
>    back to userspace to "fill in" a dynamic listing.
>    basically, vop_readdir will optionally dispatch
>    back to userland for this.
>
> I'd like to reduce code duplication.  Pseudofs looks
> like a great starting point.=20

You can probably use the pseudofs code as a starting point for autofs,
but I don't think it's a good idea to build autofs on top of pseudofs,
unless you start by greatly generalizing pseudofs: instead of
pfstype_procdir, you'd have pfstype_dynamic and custom callbacks to
handle readdir and lookup.  That actually sounds like a good idea...  a
lot of work, though.

DES
--=20
Dag-Erling Sm=C3=B8rgrav - des@des.no