Problems with dma_alloc_coherent()

Dan Malek dan at
Fri Apr 2 02:51:22 EST 2004

John Whitney wrote:

> To that end, I am submitting the attached patch which modifies
> dma_alloc_coherent() and dma_free_coherent() to do just this for
> cache-coherent platforms.

I think you should change/implement consistent_alloc()/free() to do
the right thing rather that use the #ifdef here.  Also, ensure the
ancillary function (like the dma sync/sg functions) work properly as
well.  They are probably no-ops (well, not the sg functions) but
look for those anyway.

There are also reasons to allocate un-cached DMA regions on
cache coherent platforms (but I will not debate the value in doing so),
so keep that under consideration.


	-- Dan

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