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Message-ID: <771236a2-b746-368d-f15f-23585f760ebd@acm.org>
Date:   Mon, 23 Jan 2023 11:47:23 -0800
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Subject: Re: [LSF/MM/BPF proposal]: Physr discussion
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To:     Jason Gunthorpe <jgg@nvidia.com>,
        Matthew Wilcox <willy@infradead.org>
Cc:     lsf-pc@lists.linuxfoundation.org, linux-mm@kvack.org,
        iommu@lists.linux.dev, linux-rdma@vger.kernel.org,
        Christoph Hellwig <hch@lst.de>,
        Joao Martins <joao.m.martins@oracle.com>,
        John Hubbard <jhubbard@nvidia.com>,
        Logan Gunthorpe <logang@deltatee.com>,
        Ming Lei <ming.lei@redhat.com>, linux-block@vger.kernel.org,
        netdev@vger.kernel.org, dri-devel@lists.freedesktop.org,
        nvdimm@lists.linux.dev, Shakeel Butt <shakeelb@google.com>
References: <Y8v+qVZ8OmodOCQ9@nvidia.com>
 <Y84OyQSKHelPOkW3@casper.infradead.org> <Y86PRiNCUIKbfUZz@nvidia.com>
From:   Bart Van Assche <bvanassche@acm.org>
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On 1/23/23 05:44, Jason Gunthorpe wrote:
> I've gone from quite a different starting point - I've been working
> DMA API upwards, so what does the dma_map_XX look like, what APIs do
> we need to support the dma_map_ops implementations to iterate/etc, how
> do we form and return the dma mapped list, how does P2P, with all the
> checks, actually work, etc. These help inform what we want from the
> "phyr" as an API.

I'm interested in this topic. I'm wondering whether eliminating 
scatterlists could help to make the block layer faster.

Thanks,

Bart.