Re: xen_create_contiguous_region - Regarding

[Keir Fraser <keir@xensource.com>]

On 10/4/07 07:25, "Jambunathan K" <jambunathan@netxen.com> wrote:

> xen_create_contiguous_region (as in Xen-3.0.4) can be instructed to make
> 2 kinds of allocations - from either MEMZONE_DOM or MEMZONE_DMADOM. Two
> zones are delineated by max_dma_mfn as dictated by dma_size.
> 
> A "MEMF_dma" request to __alloc_domheap_pages is assured to be satisfied
> from the MEMZONE_DMADOM.
> 
> The role of address_bits apparently stops at discreetly choosing between
> one of the above 2 zones.

This is an implementation detail inside the hypervisor. The fact that Xen
3.0.4 actually doesn't track each separate bit-width of memory separately
should not affect your use of the guest memory-allocation interfaces. The
fact that when you try to allocate 35-bit memory you actually are limited to
31-bit memory is simply a limitation you'll have to work with for 3.0.4. Xen
3.0.5 will not have this limitation.

 -- Keir