Messages in this thread | | | Date | Thu, 13 Nov 2014 16:18:16 +0900 | From | Gioh Kim <> | Subject | Why does ion_cma_allocate need GFP_HIGHUSER | __GFP_ZERO flags? |
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Hi,
I'm wondering why dma_alloc_coherent needs GFP_HIGHUSER | __GFP_ZERO flags in ion_cma_allocate().
I think dma_alloc_coherent can go to __dma_alloc if the system has CMA area. If __GFP_WAIT flag is set, it allocates memory from atomic pool. So I think calling dma_alloc_coherent with __GFP_WAIT is enough.
And can I get zero-filled-memory from CMA if I set __GFP_ZERO?
-- Thanks, Gioh Kim
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