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Date: Tue, 28 Jul 2015 22:12:21 +0100
From: Andrew Cooper <andrew.cooper3@citrix.com>
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To: "H. Peter Anvin" <hpa@zytor.com>, Julien Grall <julien.grall@citrix.com>,
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Subject: Re: [Xen-devel] [PATCH 0/8] Use correctly the Xen memory terminologies
 in Linux
References: <1438095769-2560-1-git-send-email-julien.grall@citrix.com>
 <55B7EECD.8050605@zytor.com>
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On 28/07/15 22:06, H. Peter Anvin wrote:
> On 07/28/2015 08:02 AM, Julien Grall wrote:
>> Hi all,
>>
>> This patch series aims to use the memory terminologies described in
>> include/linux/mm.h [1] for Linux xen code.
>>
>> Linux is using mistakenly MFN when GFN is meant, I suspect this is because the
>> first support of Xen was for PV. This has brought some misimplementation
>> of memory helpers on ARM and make the developper confused about the expected
>> behavior.
>>
>> For instance, with pfn_to_mfn, we expect to get a MFN based on the name.
>> Although, if we look at the implementation on x86, it's returning a GFN.
>> Most of the callers are also using it this way.
>>
>> The first 2 patches of this series is ARM related in order to remove
>> PV specific helpers which should not be used and fixing the implementation of
>> pfn_to_mfn.
>>
>> The rest of the series is here rename most of the usage in the common code
>> of MFN to GFN. I also took the opportunity to replace most of the call to
>> pfn_to_gfn in the common code by page_to_gfn avoid construction such
>> as pfn_to_gfn(page_to_pfn(...).
>>
>> Note the one xen-blkfront will be dropped by 64K series [2], I can include it
>> if necessary.
>>
> Can we actually get some documentation for Xen before starting to change
> names around?

http://xenbits.xen.org/gitweb/?p=xen.git;a=commitdiff;h=e758ed14f390342513405dd766e874934573e6cb

~Andrew