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To: Luigi Rizzo <rizzo@icir.org>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Thu, 14 Jul 2005 18:13:56 PDT."
	<20050714181356.A58300@xorpc.icir.org> 
Date: Fri, 15 Jul 2005 08:43:17 +0200
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Cc: Robert Watson <rwatson@freebsd.org>, s223560@studenti.ing.unipi.it,
	current@freebsd.org
Subject: Re: location of bioq lock 
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In message <20050714181356.A58300@xorpc.icir.org>, Luigi Rizzo writes:

>Anyways there might be a way out...
>requests go from dev_strategy()

The right place for this is geom_disk.c:g_disk_start() and the start
routines of the drivers which do not use geom_disk.

The easiest way to handle it would be to set a flag on the g_provider
saying "no more", have g_down spill the requests into a side queue
and when the driver is ready again, it calls some function which 
pulls the request out of the side queue again.


-- 
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.