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Date: Tue, 9 Oct 2012 19:21:00 +0200
From: Christoph Hellwig <hch@lst.de>
Message-ID: <20121009172100.GA23380@lst.de>
References: <00c501cda602$583de850$08b9b8f0$@cn.fujitsu.com>
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Subject: Re: [Qemu-devel] [PATCH] Use SCSI command to get size of SG device
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To: Chen HanXiao <chenhanxiao@cn.fujitsu.com>
Cc: qemu-devel@nongnu.org

On Tue, Oct 09, 2012 at 05:42:01PM +0800, Chen HanXiao wrote:
> When we use SCSI generic device as disk image, function lseek
> could not get the size of this kind of device.
> So try to use SCSI command Read Capacity(10) when lseek failed to get
> the size of SCSI generic device.

Eww, this is ugly as hell.  Why would you even need the size for a raw
passthrough device?