From mboxrd@z Thu Jan  1 00:00:00 1970
From: Guy Shattah <sguy-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>
Subject: Re: [RFC PATCH 3/3] mm/map_contig: Add mmap(MAP_CONTIG) support
Date: Mon, 16 Oct 2017 14:09:03 +0300
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On 16/10/2017 13:33, Michal Nazarewicz wrote:
> On Sun, Oct 15 2017, Guy Shattah wrote:
>> Why have several driver specific implementation if you can generalize
>> the idea and implement an already existing POSIX standard?
> Why is there a need for contiguous allocation?

This was explained in detail during a talk delivered by me and 
Christopher Lameter
during Plumbers conference 2017 @ 
https://linuxplumbersconf.org/2017/ocw/proposals/4669
Please see the slides there.

> If generalisation is the issue, then the solution is to define a common
> API where user-space can allocate memory *in the context of* a device.
> This provides a ‘give me memory I can use for this device’ request which
> is what user space really wants.
Do you suggest to add a whole new common API instead of merely adding a 
flag to existing one?