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Subject: Re: [Qemu-devel] [PATCH v2 0/7] APIC/IOAPIC cleanup
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To: Anthony Liguori <anthony@codemonkey.ws>
Cc: Blue Swirl <blauwirbel@gmail.com>, "Liu >> \"Liu,
	Jinsong\"" <jinsong.liu@intel.com>, qemu-devel <qemu-devel@nongnu.org>, Markus Armbruster <armbru@redhat.com>, Paul Brook <paul@codesourcery.com>

  On 08/23/2010 04:48 PM, Anthony Liguori wrote:
>>> The fundamental issue is: every function (minus trivial ones) in the 
>>> device models code should have a state reference.  That state 
>>> reference should inherit from a DeviceState.  If this statement 
>>> isn't true, then the device has been modelled in qdev incorrectly.
>>>
>>> Using this test, quite a lot of the "converted" devices are being 
>>> modelled incorrectly.
>>
>> Is a "state reference" allowed to have a pointer to the state, or 
>> reach it in some other way (for example, static storage for singleton 
>> devices)?
>
>
> No.  If this was C++, then the statement would be: device have to be 
> implemented in terms of objects that inherit from Device.  Device is 
> our common base object.

so,

     struct MyDevicestate {
         struct DeviceState device_state;
         bool *some_bit;
     };

bad, while

     struct MyDevicestate {
         struct DeviceState device_state;
         bool some_bit;
     };

good?

>
>> Isn't "save/restore works" an equivalent statement to "device state 
>> is reachable from the DeviceState"?
>
> I'm not sure I can connect the dots here as I'm not sure what follows 
> if your assertion is true.

If save/restore works then all state is reachable from one point?  
Presumable DeviceState?

I really don't see why the state has to be in the DeviceState subclass.  
We're probably talking past each other here due to some confusion in terms.

-- 
error compiling committee.c: too many arguments to function