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	id 4F89A68C4E; Wed, 13 May 2026 10:11:47 +0200 (CEST)
Date: Wed, 13 May 2026 10:11:47 +0200
From: Christoph Hellwig <hch@lst.de>
To: Pavel Begunkov <asml.silence@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>, Keith Busch <kbusch@kernel.org>,
	Christoph Hellwig <hch@lst.de>, Sagi Grimberg <sagi@grimberg.me>,
	Alexander Viro <viro@zeniv.linux.org.uk>,
	Christian Brauner <brauner@kernel.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Sumit Semwal <sumit.semwal@linaro.org>,
	Christian =?iso-8859-1?Q?K=F6nig?= <christian.koenig@amd.com>,
	linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-nvme@lists.infradead.org, linux-fsdevel@vger.kernel.org,
	io-uring@vger.kernel.org, linux-media@vger.kernel.org,
	dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org,
	Nitesh Shetty <nj.shetty@samsung.com>,
	Kanchan Joshi <joshi.k@samsung.com>,
	Anuj Gupta <anuj20.g@samsung.com>,
	Tushar Gohad <tushar.gohad@intel.com>,
	William Power <william.power@intel.com>,
	Phil Cayton <phil.cayton@intel.com>,
	Jason Gunthorpe <jgg@nvidia.com>
Subject: Re: [PATCH v3 02/10] iov_iter: add iterator type for dmabuf maps
Message-ID: <20260513081147.GB5477@lst.de>
References: <cover.1777475843.git.asml.silence@gmail.com> <20a233d2f35274817aa643cc0fe113707eb47e72.1777475843.git.asml.silence@gmail.com>
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User-Agent: Mutt/1.5.17 (2007-11-01)

On Wed, Apr 29, 2026 at 04:25:48PM +0100, Pavel Begunkov wrote:
> Introduce a new iterator type for dmabuf maps. The map in an opaque
> object with internals and format specific to the subsystem / driver, and
> only it can use that subsystem / driver for issuing IO. The task of the
> middle layers is to pass the map / iterator further down, maybe doing
> basic splitting and length checking. The iterator can only be used by
> operations of the file the associated map was created for.

Nice, this ended up way simpler than what I would have imagined.

Reviewed-by: Christoph Hellwig <hch@lst.de>