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Date: Thu, 11 Sep 2025 09:02:11 -0400
From: Keith Busch <kbusch@kernel.org>
To: Ming Lei <ming.lei@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>,
	Caleb Sander Mateos <csander@purestorage.com>,
	Keith Busch <kbusch@meta.com>, io-uring@vger.kernel.org
Subject: Re: [RFC PATCHv2 1/1] io_uring: add support for
 IORING_SETUP_SQE_MIXED
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References: <20250904192716.3064736-1-kbusch@meta.com>
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 <8cb8a77e-0b11-44ba-8207-05a53dbb8b9b@kernel.dk>
 <aMIv4zFIJVj-dza5@fedora>
 <aMIxmiGv5D0GvSro@fedora>
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In-Reply-To: <aMIxmiGv5D0GvSro@fedora>

On Thu, Sep 11, 2025 at 10:19:06AM +0800, Ming Lei wrote:
> On Thu, Sep 11, 2025 at 10:11:47AM +0800, Ming Lei wrote:
> > SQE128 is used for uring_cmd only, so it could be one uring_cmd
> > private flag. However, the implementation may be ugly and fragile.
> 
> Or in case of IORING_SETUP_SQE_MIXED, IORING_OP_URING_CMD is always interpreted
> as plain 64bit SQE, also add IORING_OP_URING_CMD128 for SQE128 only.

Maybe that's good enough, but I was looking for more flexibility to have
big SQEs for read/write too. Not that I have a strong use case for it
now, but in hindsight, that's where "io_uring_attr_pi" should have been
placed instead of outide the submission queue.