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Subject: Re: [PATCH V8 5/9] vDPA: introduce vDPA bus
To:     Jason Gunthorpe <jgg@mellanox.com>
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References: <20200325082711.1107-1-jasowang@redhat.com>
 <20200325082711.1107-6-jasowang@redhat.com>
 <20200325122949.GW13183@mellanox.com>
From:   Jason Wang <jasowang@redhat.com>
Message-ID: <a1474a55-7525-7c3e-a806-e3f53850a590@redhat.com>
Date:   Thu, 26 Mar 2020 13:51:41 +0800
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On 2020/3/25 =E4=B8=8B=E5=8D=888:29, Jason Gunthorpe wrote:
> On Wed, Mar 25, 2020 at 04:27:07PM +0800, Jason Wang wrote:
>> +struct vdpa_device *__vdpa_alloc_device(struct device *parent,
>> +					const struct vdpa_config_ops *config,
>> +					size_t size);
>> +
>> +#define vdpa_alloc_device(dev_struct, member, parent, config)   \
>> +			  container_of(__vdpa_alloc_device( \
>> +				       parent, config, \
>> +				       sizeof(struct dev_struct) + \
>> +				       BUILD_BUG_ON_ZERO(offsetof( \
>> +				       struct dev_struct, member))), \
>> +				       struct dev_struct, member)
> This all looks robust now, one minor remark is to not do 'struct
> dev_struct' here so the caller has to do
>
>     vdpa_alloc_device(struct foo, vpda, ...)
>
> Which suggests to the reader something unusual is happening
>
> Jason


Yes, that's better.

But my understanding is that this can be done on top.

Thanks