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Date: Tue, 7 May 2024 13:48:38 -0300
From: Jason Gunthorpe <jgg@ziepe.ca>
To: Mina Almasry <almasrymina@google.com>
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Subject: Re: [RFC PATCH net-next v8 02/14] net: page_pool: create hooks for
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On Tue, May 07, 2024 at 09:42:05AM -0700, Mina Almasry wrote:

> 1. Align with devmem TCP to use udmabuf for your io_uring memory. I
> think in the past you said it's a uapi you don't link but in the face
> of this pushback you may want to reconsider.

dmabuf does not force a uapi, you can acquire your pages however you
want and wrap them up in a dmabuf. No uapi at all.

The point is that dmabuf already provides ops that do basically what
is needed here. We don't need ops calling ops just because dmabuf's
ops are not understsood or not perfect. Fixup dmabuf.

If io_uring wants to take its existing memory pre-registration it can
wrap that in a dmbauf, and somehow pass it to the netstack. Userspace
doesn't need to know a dmabuf is being used in the background.

Jason