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From:   David Stevens <stevensd@chromium.org>
Date:   Wed, 26 Feb 2020 12:56:58 +0900
Message-ID: <CAD=HUj7h1d8dXG94FUtj4fmeUvUM0dm6NW8WHGZAceHae0zGLw@mail.gmail.com>
Subject: Re: [virtio-dev] Re: [PATCH 1/2] virtio: add dma-buf support for
 exported objects
To:     Gerd Hoffmann <kraxel@redhat.com>
Cc:     David Airlie <airlied@linux.ie>, Daniel Vetter <daniel@ffwll.ch>,
        "Michael S . Tsirkin" <mst@redhat.com>,
        Jason Wang <jasowang@redhat.com>,
        Sumit Semwal <sumit.semwal@linaro.org>,
        linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org,
        virtualization@lists.linux-foundation.org,
        Linux Media Mailing List <linux-media@vger.kernel.org>,
        linaro-mm-sig@lists.linaro.org, virtio-dev@lists.oasis-open.org
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On Tue, Feb 25, 2020 at 3:10 PM Gerd Hoffmann <kraxel@redhat.com> wrote:
>
> On Wed, Feb 19, 2020 at 05:06:36PM +0900, David Stevens wrote:
> > This change adds a new flavor of dma-bufs that can be used by virtio
> > drivers to share exported objects. A virtio dma-buf can be queried by
> > virtio drivers to obtain the UUID which identifies the underlying
> > exported object.
>
> That duplicates a bunch of code from dma-buf.c in virtio_dma_buf.c.
>
> How about dma_buf_{get,set}_uuid, simliar to dma_buf_set_name?

While I'm not opposed to such an API, I'm also hesitant to make
changes to the dma-buf API for a single use case.

As for the duplicated code around virtio_dma_buf_export_info, it can
be removed by sacrificing a little bit of type safety, if that's
preferable.

-David