From mboxrd@z Thu Jan  1 00:00:00 1970
From: Xiaofeng Ling <xiaofeng.ling@intel.com>
Subject: Re: [PATCH]blkfront change to support unmodified linux
Date: Mon, 05 Sep 2005 17:02:12 +0800
Message-ID: <431C0994.1040809@intel.com>
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	<2cae6cf4b5de67a507637b24023d79b9@cl.cam.ac.uk>
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To: Keir Fraser <Keir.Fraser@cl.cam.ac.uk>
Cc: Ian Pratt <m+Ian.Pratt@cl.cam.ac.uk>, xen-devel <xen-devel@lists.xensource.com>
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Keir Fraser wrote:
> 
> On 5 Sep 2005, at 06:41, Xiaofeng Ling wrote:
> 
>> This patch is to make blkfront can work both in xen-linux and in
>> unmodified guest which is shadow_model_translate enabled.
> 
> 
> phys == machine from the p.o.v. of a shadow-translated guest, so why not 
> modify virt_to_mfn and friends appropriately?

Sorry, I don't catch your meaning.
vmx guest is in shadow-translate mode, and gpfn need to translate to mfn 
in hypervisor. see the macro:

#define __gpfn_to_mfn(_d, gpfn)                        \
     ({                                                 \
         ASSERT(current->domain == (_d));               \
         (shadow_mode_translate(_d))                    \
         ? get_mfn_from_pfn(gpfn)                \
         : (gpfn);                                      \
     })

#define __gpfn_to_mfn_foreign(_d, gpfn)                \
     ( (shadow_mode_translate(_d))                      \
       ? gpfn_to_mfn_foreign(_d, gpfn)                  \
       : (gpfn) )

So I rename virt_to_mfn to virt_to_xfn which means if not in shadow 
translate mode, it will do translate in guest. for vmx guest, don't need 
the translation in guest. What is your suggestion?