Re: [Qemu-devel] [PATCH 2/4] block: add block topology options

[Christoph Hellwig <hch@lst.de>]

On Wed, Feb 03, 2010 at 01:00:47PM -0600, Anthony Liguori wrote:
> But I don't think this is the wrong place to do it.  The 
> BlockDriverState reflects that backing device, not the emulated device 
> itself.  In this case, you're trying to set a property of the emulated 
> device.

I think that's very borderline.  While the emulated device exposes these
properties, they are in fact a property of the backing storage, the
right sector and min/max I/O sizes are determined by the backing storage
device.

> I think these need to be qdev properties of the respective devices.  
> From a UI perspective, you can still expose -drive options for the end 
> user to consume, but this data should be associated with the devices 
> themselves.

In addition to not really beeing more logical this would be a lot more
effort.  We'd need to add properties to all the device, which means
including dealing with the n+1 ide variants, the virtio-pci proxy, etc.

If you believe it really needs to be in the qdev properties I'll
implement it, but I suspect the current version is a better idea.