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Date: Thu, 13 Jul 2023 04:15:16 -0700
From: Christoph Hellwig <hch@infradead.org>
To: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Cc: virtualization@lists.linux-foundation.org,
	"Michael S. Tsirkin" <mst@redhat.com>,
	Jason Wang <jasowang@redhat.com>,
	"David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
	Alexei Starovoitov <ast@kernel.org>,
	Daniel Borkmann <daniel@iogearbox.net>,
	Jesper Dangaard Brouer <hawk@kernel.org>,
	John Fastabend <john.fastabend@gmail.com>, netdev@vger.kernel.org,
	bpf@vger.kernel.org, Christoph Hellwig <hch@infradead.org>
Subject: Re: [PATCH vhost v11 05/10] virtio_ring: introduce
 virtqueue_dma_dev()
Message-ID: <ZK/cxNHzI23I6efc@infradead.org>
References: <20230710034237.12391-1-xuanzhuo@linux.alibaba.com>
 <20230710034237.12391-6-xuanzhuo@linux.alibaba.com>
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	lindbergh.monkeyblade.net

On Mon, Jul 10, 2023 at 11:42:32AM +0800, Xuan Zhuo wrote:
> Added virtqueue_dma_dev() to get DMA device for virtio. Then the
> caller can do dma operation in advance. The purpose is to keep memory
> mapped across multiple add/get buf operations.

This is just poking holes into the abstraction..