From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@redhat.com>
Subject: Re: [PATCH 06/15] memory: use refcnt to manage MemoryRegion
Date: Wed, 08 Aug 2012 12:20:20 +0300
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Cc: qemu-devel@nongnu.org, kvm@vger.kernel.org,
	Anthony Liguori <anthony@codemonkey.ws>,
	Jan Kiszka <jan.kiszka@siemens.com>,
	Marcelo Tosatti <mtosatti@redhat.com>,
	Stefan Hajnoczi <stefanha@gmail.com>,
	Paolo Bonzini <pbonzini@redhat.com>,
	Blue Swirl <blauwirbel@gmail.com>,
	=?ISO-8859-1?Q?Andreas_F=E4rber?= <afaerber@suse.de>
To: Liu Ping Fan <qemulist@gmail.com>
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On 08/08/2012 09:25 AM, Liu Ping Fan wrote:
> From: Liu Ping Fan <pingfank@linux.vnet.ibm.com>
> 
> Using refcnt for mr, so we can separate mr's life cycle management
> from refered object.
>   When mr->ref 0->1, inc the refered object.
>   When mr->ref 1->0, dec the refered object.
> 
> The refered object can be DeviceStae, another mr, or other opaque.

Please explain the motivation more fully.

Usually a MemoryRegion will be embedded within some DeviceState, or its
lifecycle will be managed by the DeviceState.  So long as we keep the
DeviceState alive all associated MemoryRegions should be alive as well.
 Why not do this directly?


-- 
error compiling committee.c: too many arguments to function