Re: [PATCH 04/10] swiotlb: remove the overflow buffer

From: Catalin Marinas
Date: Fri Oct 12 2018 - 13:04:18 EST


On Mon, Oct 08, 2018 at 10:02:40AM +0200, Christoph Hellwig wrote:
> Like all other dma mapping drivers just return an error code instead
> of an actual memory buffer. The reason for the overflow buffer was
> that at the time swiotlb was invented there was no way to check for
> dma mapping errors, but this has long been fixed.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> ---
> arch/arm64/mm/dma-mapping.c | 2 +-
> arch/powerpc/kernel/dma-swiotlb.c | 4 +--
> include/linux/dma-direct.h | 2 ++
> include/linux/swiotlb.h | 3 --
> kernel/dma/direct.c | 2 --
> kernel/dma/swiotlb.c | 59 ++-----------------------------
> 6 files changed, 8 insertions(+), 64 deletions(-)

I went through the patches and they look fine to me (with the vunmap
fix for the last patch). For the arm64 bits:

Acked-by: Catalin Marinas <catalin.marinas@xxxxxxx>