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Subject: Re: [BK-2.5] Update the generic DMA API to take GFP_ flags on
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From: James Bottomley <James.Bottomley@steeleye.com>
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> What about platforms that can only use GFP_ATOMIC due to
> implementation side issues?  Is that "OK"?

Yes.

A GFP_KERNEL request is safely implemented as GFP_ATOMIC as long as the caller 
checks return for NULL.  for dma_alloc_coherent return checking is a 
requirement because the system may return NULL anyway if it is out of mappings 
even with a GFP_KERNEL flag.

James