Re: [BK-2.5] Update the generic DMA API to take GFP_ flags on

From: David S. Miller (davem@redhat.com)
Date: Tue Jan 14 2003 - 10:30:23 EST


   From: James Bottomley <James.Bottomley@steeleye.com>
   Date: Tue, 14 Jan 2003 10:30:15 -0500

   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.
   
Now what about the corollary, a platform that needs
to sleep to setup the cpu mapings in a race-free manner?

It could not ever honor GFP_ATOMIC in that case.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/



This archive was generated by hypermail 2b29 : Wed Jan 15 2003 - 22:00:50 EST