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To be ab= le >>> to give out DMA handles, the view type contains both CPU and DMA pointe= rs, >>> and the projection method projects both at once. >>> >>> Delegate most of the `Io` implementation to `SysMemBackend`. Provide a >>> method to erase the DMA handle and give out a `SysMem` view, if the use= r >>> does not need the `dma_handle`. >>> >>> Signed-off-by: Gary Guo >> >> Of the Sashiko comments, the second one (adding exclusivity requirement >> to the safety comment) looks actionable; with that: > > Most of the text is taken from existing `as_mut` method on the full `Cohe= rent`. > I think these can be addressed, but I'd prefer to leave it to a further p= atch > (perhaps as a good first issue). For this an acceptable fix would be to add a sentence to the safety comment of `as_mut` saying that the caller is responsible for ensuring there is no concurrent access - I suspect you are talking about something different for a good first issue.