From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: [PATCH] virtio-spec: add field for scsi command size
Date: Wed, 19 Jun 2013 12:21:27 +0300
Message-ID: <20130619092127.GB2816@redhat.com>
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	<20130619082417.GA2558@redhat.com> <51C16BC2.2060302@redhat.com>
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To: Paolo Bonzini <pbonzini@redhat.com>
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On Wed, Jun 19, 2013 at 10:28:50AM +0200, Paolo Bonzini wrote:
> Il 19/06/2013 10:24, Michael S. Tsirkin ha scritto:
> >> > 2) We introduce VIRTIO_NET_F_ANY_LAYOUT and VIRTIO_BLK_F_ANY_LAYOUT
> >> >    specifically for net and block (note the new names).
> 
> So why not a transport feature?  Is it just because the SCSI commands
> for virtio-blk also require a config space field?  Sorry if I missed
> this upthread.
> 
> Paolo

One of the reasons is we've run out of transport features :)

> >> > 3) I note the special case of stupid descriptors.
> >> > 4) Enjoy our humble pie, don't hide it in a footnote!
> >> > 
> >> > If that seems OK, I'll modify the net and block specs appropriately.
> >> > 
> >> > Cheers,
> >> > Rusty.
> > Acked-by: Michael S. Tsirkin <mst@redhat.com>
> > 
> > an additional suggestion: limit max s/g
> > to vq size (it's in theory possible to go higher with indirect
> > descriptors, but we need some limit, and queue size gives us
> > a nice way to say "this is a max descriptor size").