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Subject: [Qemu-devel] Re: [PATCH v3 1/1] Shared memory uio_pci driver
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To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Cam Macdonell <cam@cs.ualberta.ca>, qemu-devel@nongnu.org, kvm@vger.kernel.org

On 03/28/2010 12:40 PM, Michael S. Tsirkin wrote:
>>> uio accepts 32 bit writes to the char device file. We can encode
>>> the fd number there, and use the high bit to signal assign/deassign.
>>>
>>>        
>> Ugh.  Very unexpandable.
>>      
> It currently fails on any non-4 byte write.
> So if we need more bits in the future we can always teach it
> about e.g. 8 byte writes.
>
> Do you think it's worth it doing it now already, and using
> 8 byte writes for msi mapping?
>    

Aren't ioctls a lot simpler?

Multiplexing multiple functions on write()s is just ioctls done uglier.

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