Messages in this thread | | | Date | Mon, 9 Sep 2002 11:13:55 -0700 | From | Jesse Barnes <> | Subject | Re: Calculating kernel logical address .. |
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On Mon, Sep 09, 2002 at 02:00:35PM -0400, Richard B. Johnson wrote: > Well I just read Documentation/DMA-mapping.txt as advised by David > and it seems as though it will no longer be possible to do what > many programmers have been wanting to do, to wit: > > (1) In user-code, allocate a buffer. > (2) Lock that buffer into memory. > (3) Call some driver that DMAs data to/from that buffer.
It looks drivers/media/video/video-buf.c uses alloc_kiovec() and map_user_kiobuf() to do it. And I think Ben LaHaise was talking about removing these functions and creating some other, lightweight interface for the same purpose? OTOH, it's been awhile since I looked at this stuff, so I'm not sure how it works anymore, I'm sure someone else could provide more useful info.
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