[PATCH v6 RESED 1/2] dma: replace zone_dma_bits by zone_dma_limit

Catalin Marinas catalin.marinas at arm.com
Mon Aug 12 04:22:10 PDT 2024


On Sun, Aug 11, 2024 at 10:09:35AM +0300, Baruch Siach wrote:
> From: Catalin Marinas <catalin.marinas at arm.com>
> 
> Hardware DMA limit might not be power of 2. When RAM range starts above
> 0, say 4GB, DMA limit of 30 bits should end at 5GB. A single high bit
> can not encode this limit.
> 
> Use plain address for DMA zone limit.
> 
> Since DMA zone can now potentially span beyond 4GB physical limit of
> DMA32, make sure to use DMA zone for GFP_DMA32 allocations in that case.
> 
> Signed-off-by: Catalin Marinas <catalin.marinas at arm.com>
> Co-developed-by: Baruch Siach <baruch at tkos.co.il>
> Signed-off-by: Baruch Siach <baruch at tkos.co.il>

You might want to say that no functional change is expected with this
patch. The patch looks fine.

Reviewed-by: Catalin Marinas <catalin.marinas at arm.com>



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