On Wed, May 5, 2021 at 3:38 PM Joao Martins [off-list ref] wrote:
On 5/5/21 11:34 PM, Dan Williams wrote:
quoted
On Thu, Mar 25, 2021 at 4:10 PM Joao Martins [off-list ref] wrote:
quoted
@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."