From: Anthony Liguori <anthony@codemonkey.ws>
To: Markus Armbruster <armbru@redhat.com>
Cc: "Stefan Hajnoczi" <stefanha@gmail.com>,
"Andreas Färber" <afaerber@suse.de>,
qemu-devel@nongnu.org, "Evgeny Voevodin" <e.voevodin@samsung.com>,
"Paolo Bonzini" <pbonzini@redhat.com>
Subject: Re: [Qemu-devel] Can we improve virtio data structures with QOM?
Date: Fri, 01 Jun 2012 16:12:16 +0800 [thread overview]
Message-ID: <4FC87960.2090206@codemonkey.ws> (raw)
In-Reply-To: <m38vg8i9em.fsf@blackfin.pond.sub.org>
On 06/01/2012 12:48 AM, Markus Armbruster wrote:
> Anthony Liguori<anthony@codemonkey.ws> writes:
>
> [On how to model virtio devices in QOM:]
>> Basically, it should look like:
>>
>> VirtioPCIDevice is-a PCIDevice
>>
>> VirtioPCIDevice has-a link<VirtioDevice>
>
> Could you explain why this is link<> and not child<>?
So you can do:
qemu -device virtio-pci,id=foo,vdev=bar -device virtio-blk,id=bar,bus=foo
The alternative would be:
qemu -device virtio-pci,id=foo,child_type=virtio-blk
But that feels ugly to me. If you want to have a variable type of device, a
link is the right tool.
BTW, I make no mention of BusState here. That's intentional. There's no need
to involve buses IMHO.
Regards,
Anthony Liguori
>
>> VirtioDevice is-a DeviceState
>>
>> VirtioBlk is-a VirtioDevice
>> VirtioNet is-a VirtioDevice
>> ...
>>
>> VirtioPCIBlk is-a VirtioPCIDevice
>> VirtioPCIBlk has-a child<VirtioBlk>
>>
>> This gives us backwards compat while also providing a cleaner
>> model. VirtioPCIBlk et al would be deprecated eventually (but not any
>> time soon).
next parent reply other threads:[~2012-06-01 8:12 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <m3txyx514d.fsf@blackfin.pond.sub.org>
[not found] ` <CAJSP0QVSaRvr-13o=o7pZ2UL999C+yim=fFE_iBoLA--BC9_-g@mail.gmail.com>
[not found] ` <m3pq9lfxb0.fsf@blackfin.pond.sub.org>
[not found] ` <4FC6A71A.90303@codemonkey.ws>
[not found] ` <m38vg8i9em.fsf@blackfin.pond.sub.org>
2012-06-01 8:12 ` Anthony Liguori [this message]
2012-06-01 9:25 ` [Qemu-devel] Can we improve virtio data structures with QOM? Markus Armbruster
2012-06-01 9:32 ` Anthony Liguori
2012-06-01 11:43 ` Markus Armbruster
2012-06-02 9:31 ` Anthony Liguori
2012-06-04 16:40 ` Markus Armbruster
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=4FC87960.2090206@codemonkey.ws \
--to=anthony@codemonkey.ws \
--cc=afaerber@suse.de \
--cc=armbru@redhat.com \
--cc=e.voevodin@samsung.com \
--cc=pbonzini@redhat.com \
--cc=qemu-devel@nongnu.org \
--cc=stefanha@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).