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Date: Thu, 22 May 2003 03:51:19 -0700
From: David Schultz <das@FreeBSD.ORG>
To: Peter Edwards <pmedwards@eircom.net>
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Subject: Re: Question on (ab)using the swap pager and VM
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On Wed, May 21, 2003, Peter Edwards wrote:
> Hi All,
> As a programming exercise, I'm trying to write what is in essence
> a synthetic filesystem where the synthetic files contain large
> amounts of data I want to use a swap pager as a cached store for
> the data I'm providing. (ie, it'll be generated in the kernel)

Have you taken a look at md(4)?  This driver provides the
swap-backed functionality you want at the block device level where
it should be.  If you really want to duplicate the functionality,
though, take a look at how md(4) does it.  Specifically, look at
mdcreate_swap().