From mboxrd@z Thu Jan  1 00:00:00 1970
From: BVK Chaitanya <bayapuneni_chaitanya@symantec.com>
Subject: Re: about: XENMEM_machphys_mfn_list
Date: Fri, 18 Jul 2008 14:40:39 +0530
Message-ID: <48805E0F.9000208@symantec.com>
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To: "Lin.Yu" <yulin724@gmail.com>
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Lin.Yu wrote:
> 
> XENMEM_machphys_mfn_list command is used to acquire the mapping between 
> the pseudo-physical to machine. And the hypercall will fill in the 
> struct xen_machphys_mfn_list.
> 
> I do not understand "This table is an array of pseudo-physical frame 
> numbers of the start of 2MB extents, corresponding to 2MB rangs in the 
> pseudo-physical address space".
> "This table" means the array pointed by xen_machphys_mfn_list.extent_start.
> 
> I am reading the code about this struct, still in confusion.
> :-)
> Who can help me?
> 


AFAIU, here "table" is nothing more than an array of xen_pfn_ts.

Only complication is, mfns returned are `base-mfns' for 2MB memory regions.

For example, if mfn 100 is returned, it means mfns 100-612 hold the 2MB 
region (612 = 100 + 512; 512 pages make 2MB)


--
bvk-chaitanya