[Linaro-mm-sig] [PATCH 4/4] ARM: remove consistent dma region and use common vmalloc range for dma allocations
Russell King - ARM Linux
linux at arm.linux.org.uk
Fri Apr 13 18:38:13 UTC 2012
On Fri, Apr 13, 2012 at 04:05:50PM +0200, Marek Szyprowski wrote:
> This patch changes dma-mapping subsystem to use generic vmalloc areas
> for all consistent dma allocations. This increases the total size limit
> of the consistent allocations and removes platform hacks and a lot of
> duplicated code.
NAK. I don't think you appreciate the contexts from which the dma coherent
code can be called from, and the reason why we pre-allocate the page
tables (so that IRQ-based allocations work.)
The vmalloc region doesn't allow that because page tables are allocated
using GFP_KERNEL not GFP_ATOMIC.
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