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Date: Fri, 15 Dec 2023 19:01:26 -0800
From: Jakub Kicinski <kuba@kernel.org>
To: Shakeel Butt <shakeelb@google.com>
Cc: Mina Almasry <almasrymina@google.com>, Yunsheng Lin
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Subject: Re: [RFC PATCH net-next v1 4/4] net: page_pool: use netmem_t
 instead of struct page in API
Message-ID: <20231215190126.1040fa12@kernel.org>
In-Reply-To: <20231215021114.ipvdx2bwtxckrfdg@google.com>
References: <20231214020530.2267499-1-almasrymina@google.com>
	<20231214020530.2267499-5-almasrymina@google.com>
	<ddffff98-f3de-6a5d-eb26-636dacefe9aa@huawei.com>
	<CAHS8izO2nDHuxKau8iLcAmnho-1TYkzW09MBZ80+JzOo9YyVFA@mail.gmail.com>
	<20231215021114.ipvdx2bwtxckrfdg@google.com>
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On Fri, 15 Dec 2023 02:11:14 +0000 Shakeel Butt wrote:
> > From my POV it has to be the first one. We want to abstract the memory
> > type from the drivers as much as possible, not introduce N new memory
> > types and ask the driver to implement new code for each of them
> > separately.
> 
> Agree with Mina's point. Let's aim to decouple memory types from
> drivers.

What does "decouple" mean? Drivers should never convert netmem 
to pages. Either a path in the driver can deal with netmem,
i.e. never touch the payload, or it needs pages.

Perhaps we should aim to not export netmem_to_page(),
prevent modules from accessing it directly.