From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:43189) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RGoeu-0008RV-Hy for qemu-devel@nongnu.org; Thu, 20 Oct 2011 05:11:32 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1RGoet-0001hp-Hk for qemu-devel@nongnu.org; Thu, 20 Oct 2011 05:11:28 -0400 Received: from mx1.redhat.com ([209.132.183.28]:8131) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RGoet-0001h7-17 for qemu-devel@nongnu.org; Thu, 20 Oct 2011 05:11:27 -0400 Message-ID: <4E9FE674.30101@redhat.com> Date: Thu, 20 Oct 2011 11:14:28 +0200 From: Kevin Wolf MIME-Version: 1.0 References: <1319036398-14320-1-git-send-email-pbonzini@redhat.com> <1319036398-14320-2-git-send-email-pbonzini@redhat.com> In-Reply-To: <1319036398-14320-2-git-send-email-pbonzini@redhat.com> Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 1/8] vpc: detect floppy disk geometries List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: qemu-devel@nongnu.org, stefanha@linux.vnet.ibm.com Am 19.10.2011 16:59, schrieb Paolo Bonzini: > Converting a floppy image from RAW to VPC and back will generate > a zero-padded file of the wrong size, because the geometry is not > computed correctly. Special case floppy disk images, handling > standard MS-DOS capacities (160/180/320/360 for low density > 5.25" disks, 1200 for high density 5.25" disks, 720/1440/2880 > for 3.5" disks). > > Signed-off-by: Paolo Bonzini Unrelated to coroutines, isn't it? > --- > block/vpc.c | 8 ++++++++ > 1 files changed, 8 insertions(+), 0 deletions(-) > > diff --git a/block/vpc.c b/block/vpc.c > index cb6c570..549a632 100644 > --- a/block/vpc.c > +++ b/block/vpc.c > @@ -463,6 +463,14 @@ static int calculate_geometry(int64_t total_sectors, uint16_t* cyls, > { > uint32_t cyls_times_heads; > > + if (total_sectors <= 5760) { > + /* Floppy disk geometry */ Please state in the comment that this part is deviating from the algorithm in the VHD spec, which this function is generally supposed to implement. Kevin