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From: Paul Brook <paul@codesourcery.com>
Subject: Re: [Qemu-devel] Block driver and constant sector size
Date: Fri, 18 May 2007 21:41:35 +0100
References: <4645ECE2.4050408@videotron.ca>
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To: qemu-devel@nongnu.org
Cc: Jonathan Phenix <jonathan.phenix@videotron.ca>

On Saturday 12 May 2007, Jonathan Phenix wrote:
> Hi,
>
> currently the block driver in qemu only handles blocks (or sectors)
> which are 512 bytes long, 
>...
> Then, each probe functions should be modified to reject sector size
> which is not 512 bytes, except for the raw block driver, which will be
> modified to accept any block sizes. This change would probably solve the
> whole problem without having a negative impact on the rest of the code.
>
> Is it the right way to solve the problem? If this solution is accepted,
> I will code it and submit a patch.

Seems like it might just be simpler to have the qemu block ABI use bytes 
rather than blocks. Maybe with some common helper functions for doing R/M/W 
on hard sectored devices.

By adding variable sized sectors you're just shifting complexity from the 
block backends to the device emulation.

Paul