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Subject: Re: [Qemu-devel] scsi-generic and max request size
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Date: Thu, 23 Dec 2010 10:44:17 +1100
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To: Alexander Graf <agraf@suse.de>
Cc: Kevin Wolf <kwolf@redhat.com>, Christoph Hellwig <hch@infradead.org>, Hannes Reinecke <hare@suse.de>, ronnie sahlberg <ronniesahlberg@gmail.com>, qemu-devel <qemu-devel@nongnu.org>

On Thu, 2010-12-23 at 00:39 +0100, Alexander Graf wrote:
> This all belongs in the block layer. If you create a call back
> function or property in the block struct, windows can implement its
> own limits when someone sits down to implement SG_IO on Windows.

Right and we do have "generic" ways it seems to interrogate those
limits .. except they seem to be broken for "sg" :-)

Also I've spotted some oddities where the ioctl for the max request size
sometimes put_user as a int * and sometimes as a short * ... ooops...

Cheers,
Ben.