On Thu, Dec 31, 2015 at 04:50:54PM +0900, Masahiro Yamada wrote:

Hi.

I am new to the Linux DMA APIs.

First, I started by reading Documentation/DMA-API.txt,
but I am confused with the term "consistent memory".

Just read "coherent memory" instead - the documentation confusingly uses
the two terms to refer to the same thing.  I think there was a patch a
while back to replace "consistent" with "coherent" in this document,
though I'm not sure what happened to it.

I think you have answers to your other points by others in this thread.

Thanks.

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