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Date:   Wed, 12 Dec 2018 01:09:17 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     Tomasz Figa <tfiga@chromium.org>
Cc:     Christoph Hellwig <hch@infradead.org>,
        Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
        "Matwey V. Kornilov" <matwey@sai.msu.ru>,
        Linux Media Mailing List <linux-media@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        "Matwey V. Kornilov" <matwey.kornilov@gmail.com>,
        Alan Stern <stern@rowland.harvard.edu>,
        Ezequiel Garcia <ezequiel@collabora.com>, hdegoede@redhat.com,
        Hans Verkuil <hverkuil@xs4all.nl>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        rostedt@goodmis.org, mingo@redhat.com,
        Mike Isely <isely@pobox.com>,
        Bhumika Goyal <bhumirks@gmail.com>,
        Colin King <colin.king@canonical.com>,
        Kieran Bingham <kieran.bingham@ideasonboard.com>,
        keiichiw@chromium.org
Subject: Re: [PATCH v5 2/2] media: usb: pwc: Don't use coherent DMA buffers
 for ISO transfer
Message-ID: <20181212090917.GA30598@infradead.org>
References: <20180821170629.18408-1-matwey@sai.msu.ru>
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On Wed, Dec 12, 2018 at 05:57:02PM +0900, Tomasz Figa wrote:
> How about dma_sync_sg_*()? I'd expect some drivers to export/import
> such memory via sg, since that's the typical way of describing memory
> in DMA-buf.

The way it is implemented dma_sync_sg_* would just work, however there
really should be no need to have sglists for buffers created by this
API.

> Sounds good to me. Thanks for working on this. I'd be happy to be on
> CC and help with review when you post the patches later.

The patches were already posted here:

https://lists.linuxfoundation.org/pipermail/iommu/2018-December/031982.html