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Date: Tue, 18 Nov 2014 10:44:52 +0100
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Subject: Re: [Qemu-devel] [PATCH 2/5] block: Add AioContextNotifier
	functions to BB
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To: Max Reitz <mreitz@redhat.com>, qemu-devel@nongnu.org
Cc: Kevin Wolf <kwolf@redhat.com>, Peter Lieven <pl@kamp.de>, Markus Armbruster <armbru@redhat.com>, Stefan Hajnoczi <stefanha@redhat.com>

On 18/11/2014 10:26, Max Reitz wrote:
> However, when you consider (as far as I looked into it) that a BDS is
> only closed when there are either no references to it (which will not
> happen as long as it has a BB) or when it is ejected, it suddenly does
> make sense: "Ejecting" really is something for the BB, so it makes sense
> to wait for that event (even though the name "close notifier" doesn't
> sound much like it...).

I agree, and indeed the notifier was added to deal with ejection.

Thanks for clarifying.  I guess if QEMU were written in C++ we would
have a hierarchy like this:

    BlockDevice (abstract)
        BlockBackend
        BlockDriverState

and there would be no duplication of function names; the BlockBackend
implementation would still have to forward to the top BlockDriverState.

Paolo