Subject: Xen and bounce buffers
To: None <>
From: Jason Thorpe <>
List: port-xen
Date: 01/20/2005 06:56:56
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On Jan 20, 2005, at 4:31 AM, Manuel Bouyer wrote:

> Log Message:
> bus_dma(9) for xen. Derived from arch/x86/x86/bus_dma.c.
> bounce buffers not supported yet, because xen doesn't have an interface
> to request memory in a specific range (this means that DMA on ISA won't
> be supported), but I've left the code commented out because xen will
> likely provide an appropriate hypercall in the future.

This is important for more than just ISA DMA.  PCI DMA needs them on 
systems with more than 4G of RAM, if the device doesn't support dual 
address cycle.

         -- Jason R. Thorpe <>

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