Re: [Qemu-devel] Re: [PATCH 09/15] eepro100: convert to new pci interface

["Michael S. Tsirkin" <mst@redhat.com>]

On Wed, Feb 10, 2010 at 11:43:29AM +0100, Markus Armbruster wrote:
> "Michael S. Tsirkin" <mst@redhat.com> writes:
> 
> > On Wed, Feb 10, 2010 at 07:32:10AM +0100, Stefan Weil wrote:
> >> See my inline comments.
> >> 
> >> 
> >> Anthony Liguori schrieb:
> [...]
> >> > -static void pci_map(PCIDevice * pci_dev, int region_num,
> >> > -                    pcibus_t addr, pcibus_t size, int type)
> >> > +static void pci_io_write(PCIDevice *dev, pcibus_t addr, int size,
> >> > +                         uint32_t value)
> >> >  {
> >> > -    EEPRO100State *s = DO_UPCAST(EEPRO100State, dev, pci_dev);
> >> > -
> >> > -    TRACE(OTHER, logout("region %d, addr=0x%08"FMT_PCIBUS", "
> >> > -          "size=0x%08"FMT_PCIBUS", type=%d\n",
> >> > -          region_num, addr, size, type));
> >> > +    EEPRO100State *s = DO_UPCAST(EEPRO100State, dev, dev);
> >> >   
> >> 
> >> Please don't change the name of the PCIDevice pointer argument
> >> from pci_dev to dev.
> >> 
> >> This dev, dev in DO_UPCAST is ugly and misleading.
> >
> > It's a matter of taste: I actually think it's pretty: I never remember
> > which argument of DO_UPCAST is which, and if both are dev it doesn't
> > matter.
> 
> I also have trouble remembering how to use DO_UPCAST(), but playing
> games with identifiers is a poor fix for that.  I find the use of the
> same name "dev" for two different things in the same expression rather
> confusing.  Could we improve DO_UPCAST() instead?
> 
> For what it's worth, I have no trouble with container_of().  DO_UPCAST()
> takes the same arguments in a different order, which I find irritating.
> 
> [...]

IMO it would be ideal to remove offset assumptions where possible
and then we can use container_of.

-- 
MST