On 5/6/21 12:14 AM, Dan Williams wrote:
On Wed, May 5, 2021 at 3:38 PM Joao Martins
> On 5/5/21 11:34 PM, Dan Williams wrote:
>> On Thu, Mar 25, 2021 at 4:10 PM Joao Martins <joao.m.martins(a)oracle.com>
>>> @altmap is stored in a dev_pagemap, but it will be repurposed for
>>> hotplug memory for storing the memmap in the hotplugged memory[*] and
>>> reusing the altmap infrastructure to that end. This is to say that
>>> altmap can't be replaced with a @pgmap as it is going to cover more than
>>> dev_pagemap backend altmaps.
>> I was going to say, just pass the pgmap and lookup the altmap from
>> pgmap, but Oscar added a use case for altmap independent of pgmap. So
>> you might refresh this commit message to clarify why passing pgmap by
>> itself is not sufficient.
> Isn't that what I am doing above with that exact paragraph? I even
> reference his series at the end of commit description :) in [*]
Oh, sorry, it didn't hit me explicitly that you were talking about
Oscar's work I thought you were referring to your own changes in this
set. I see it now... at a minimum the tense needs updating since
Oscar's changes are in the past not the future anymore.
If it helps,
the following reads more direct to me: "In support of using compound
pages for devmap mappings, plumb the pgmap down to the
vmemmap_populate* implementation. Note that while altmap is
retrievable from pgmap the memory hotplug codes passes altmap without
pgmap, so both need to be independently plumbed."
Let me use this one instead, definitely better than my strange english :)