From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1IdTn4-00027w-AB for qemu-devel@nongnu.org; Thu, 04 Oct 2007 12:43:10 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1IdTn3-00027F-Ci for qemu-devel@nongnu.org; Thu, 04 Oct 2007 12:43:09 -0400 Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1IdTn3-00027B-5X for qemu-devel@nongnu.org; Thu, 04 Oct 2007 12:43:09 -0400 Received: from sark4.cc.gatech.edu ([130.207.7.19]) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1IdTn2-0003dN-Uo for qemu-devel@nongnu.org; Thu, 04 Oct 2007 12:43:09 -0400 Received: from sark3.cc.gatech.edu (sark3.cc.gatech.edu [130.207.7.22]) by sark4.cc.gatech.edu (8.13.6/8.12.8) with ESMTP id l94Gh8oQ004264 for ; Thu, 4 Oct 2007 12:43:08 -0400 (EDT) Received: from [192.168.0.130] (c-66-56-81-115.hsd1.ga.comcast.net [66.56.81.115]) (authenticated bits=0) by sark3.cc.gatech.edu (8.12.10/8.12.10) with ESMTP id l94Gh79i006000 (version=TLSv1/SSLv3 cipher=RC4-MD5 bits=128 verify=NOT) for ; Thu, 4 Oct 2007 12:43:08 -0400 (EDT) Message-ID: <47051824.1080607@cc.gatech.edu> Date: Thu, 04 Oct 2007 12:43:16 -0400 From: Kaushik Bhandankar MIME-Version: 1.0 Subject: Re: [Qemu-devel] Pending Disk I/O requests during live VM migration References: <47050E64.5070901@cc.gatech.edu> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Blue Swirl wrote: > On 10/4/07, Kaushik Bhandankar wrote: > >> I am trying to implement functionality in fully-virtualized xen wherein >> the responses to the pending disk I/O requests during live VM migration >> get trasnsferred to the new VMM form the old VMM. Specifically, I am >> looking at IDE disk (tools/ioemu/hw/ide.c) >> > > You should ask Xen related questions in xen lists. At least in Qemu > pending I/O are flushed before VM save in vl.c:5522. > Thanks Blue... somebody in the xen-devel list suggested to mail this list about it.... Anyway, I have some IDE related questions which somebody on this list might answer 1) I guess the IDE disk code is in ioemu/hw/ide.c. But where is the IDE disk controller code located ?? 2) I do not really understand BMDMA in ioemu/hw/ide.c. google doesnt seem to be helping much here. Any documentation about the QEMU IDE disks would be greatly appreciated. 3) vl.c:5522 seems to be not the correct code (I guess our vl.c codes are different).. Could you point me to the routine in vl.c where the pending disk IO requests are flushed before VM save (I guess the VM save happens in qemu_savevm_state() in vl.c wherein it invokes all the registered save handlers)? 4) Somebody told me that the pending disk IO requests are stored somewhere in quemu's I/O disk model but I am not sure exactly where....Can somebody help me with this ? Thanks, Kaushik