[RFC v2 1/2] dma-buf: Introduce dma buffer sharing mechanism

[Rob Clark]

On Mon, Jan 9, 2012 at 4:10 AM, InKi Dae <daeinki at gmail.com> wrote:
> note : in case of sharing a buffer between v4l2 and drm driver, the
> memory info would be copied vb2_xx_buf to xx_gem or xx_gem to
> vb2_xx_buf through sg table. in this case, only memory info is used to
> share, not some objects.

which v4l2/vb2 patches are you looking at?  The patches I was using,
vb2 holds a reference to the 'struct dma_buf *' internally, not just
keeping the sg_table

BR,
-R