Re: [Qemu-devel] Pending Disk I/O requests during live VM migration

[Kaushik Bhandankar]

Blue Swirl wrote:
> On 10/4/07, Kaushik Bhandankar <address@hidden> 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