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Subject: Re: [Qemu-devel] [PATCH 01/10] Add stub functions for PCI device
 models to do PCI DMA
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To: Anthony Liguori <anthony@codemonkey.ws>
Cc: Anthony Liguori <aliguori@us.ibm.com>, joerg.roedel@amd.com, agraf@suse.de, qemu-devel@nongnu.org, eduard.munteanu@linux360.ro, David Gibson <david@gibson.dropbear.id.au>, rth@twiddle.net

On 09/01/2011 07:32 PM, Anthony Liguori wrote:
>> True. But I still think it's the right thing.
>>
>> We can't really pass a MemoryRegion as the source address, since there
>> is no per-device MemoryRegion.
>
>
> Couldn't the PCI bus expose 255 MemoryRegions though? 

What would those mean?  A MemoryRegion is something that can respond to 
reads and writes.

> It could still use the pci_address_space I think since that should 
> include RAM too, right?
>

No.

> In fact, initially, you could have a 
> pci_bus_get_device_memory_region(bus, dev) that just returns 
> pci_address_space().
>
> You just need the memory_st[bwl] functions I think.
>

Maybe we need a different type of object here - MemoryClient or something.

-- 
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.