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Date: Tue, 22 Sep 2009 17:41:49 +0300
From: "Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: [Qemu-devel] Re: [PATCH] qemu: make virtio-blk PCI compliant
	by default
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To: Avi Kivity <avi@redhat.com>
Cc: john cooper <john.cooper@redhat.com>, Rusty Russell <rusty@rustcorp.com.au>, qemu-devel@nongnu.org, jens.axboe@oracle.com

On Tue, Sep 22, 2009 at 05:27:22PM +0300, Avi Kivity wrote:
> On 09/22/2009 05:21 PM, john cooper wrote:
>>> Can we just read this page as a virtqueue command instead of having it
>>> mapped permanently?
>>>      
>> Probably although I hadn't looked specifically
>> at doing so.   Mapping the data via an unused
>> pci bar is pretty trivial and seemed minimally
>> intrusive to the existing driver.
>>    
>
> We'll run out of bars if we expend them like that.

BAR1 is used for MSI-X already (if MSI-X is enabled), you can just add
your data there. I would report the offset within the BAR somewhere
in io space or in configuration space, so that we can relocate tables
later if we like without changing guests.

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