From owner-freebsd-current@FreeBSD.ORG  Wed Jun  1 12:57:41 2005
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To: Andre Guibert de Bruet <andy@siliconlandmark.com>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Wed, 01 Jun 2005 08:53:15 EDT."
	<20050601083308.D69811@lexi.siliconlandmark.com> 
Date: Wed, 01 Jun 2005 14:57:25 +0200
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Sender: phk@critter.freebsd.dk
Cc: Don Lewis <truckman@FreeBSD.org>, current@FreeBSD.org
Subject: Re: [RFC] [PATCH] VM & VFS changes 
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In message <20050601083308.D69811@lexi.siliconlandmark.com>, Andre Guibert de B
ruet writes:

>> This problem is a bit complicated because there can be various
>> combinations of:
>>
>> 	mounted file systems that reside on swap-backed memory disks
>>
>> 	mounted file systems that reside on vnode-backed memory disks
>>
>> 	vnode-backed memory disks used as swap devices

Maybe the simplest solution is also the best:  keep track of the
dependencies and do the cleanup leaf->root on the resulting tree.

It would not take much more than a simple data structure to let
the various pieces of code (mainly md(4) really) say "this device
depends on this other thing".

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.