[Qemu-devel] Re: [PATCH 5/8] ide/pci: convert to qdev.

[Gerd Hoffmann]

On 09/11/09 16:35, Juan Quintela wrote:
> > > > -    IDEBus bus[2];
> > > > +    IDEBus *bus[2];
>
> You notice this little thing "*" that changed?
> VMState preffers pretty much embedded arrays than pointers (arrays of
> pointers have the same problem, basically).
>
> Notice the "preffers" part.  VMState can follow pointers, just that each
> VMStateDescription is a series of offsets in one structure.  Having
> pointers brings to you all the problems associated with ioctl's with
> pointers in the middle of the payload.  It is doable, just not nice.

I don't see the problem here.

You'll need a separate VMStateDescription for a IDEBus anyway, then have 
all the ide drivers use that, just to avoid duplication.

ide will just be
  vmstate_ide_bus(bus)

pci will be something like
  vmstate_pci()
  /* busmaster stuff goes here */
  vmstate_ide_bus(bus[0])
  vmstate_ide_bus(bus[1])

I fail to see how it makes a big difference whenever the ide bus is 
referenced or embedded ...

cheers,
  Gerd