[Qemu-devel] Re: [PATCH 0/4] Block DMA helpers (v2)

[Anthony Liguori]

Avi Kivity wrote:
> The current dma mapping API is fairly complex to use: mapping can fail
> when bounce resources are exhausted, requiring the caller to reschedule,
> and the interface is fairly low level.
>
> This patchset introduces block device oriented helpers to centralize this
> logic.  Devices need only submit a scatter/gather list, and the helpers
> will do all the dirty work of mapping, rescheduling, and unmapping.  IDE
> has been converted to the new API.
>   

Applied all.  Thanks.

BTW, what are your plans for virtio?  I'd reckon that just trying to map 
the full SG list and failing gracefully if unable would be sufficient.  
You could also convert the element to contain a QEMUSGList and then make 
use of the IO helpers in virtio-blk and virtio-net.  It just gets a 
little funky for simpler things like virtio-console and virtio-balloon.

Regards,

Anthony Liguori