Re: [PATCH v2 5/8] dma-mapping: Support batch mode for dma_direct_sync_sg_for_*

[Leon Romanovsky <leon@xxxxxxxxxx>]

On Sat, Dec 27, 2025 at 11:52:45AM +1300, Barry Song wrote:
> From: Barry Song <baohua@xxxxxxxxxx>
> 
> Instead of performing a flush per SG entry, issue all cache
> operations first and then flush once. This ultimately benefits
> __dma_sync_sg_for_cpu() and __dma_sync_sg_for_device().
> 
> Cc: Leon Romanovsky <leon@xxxxxxxxxx>
> Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
> Cc: Will Deacon <will@xxxxxxxxxx>
> Cc: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
> Cc: Robin Murphy <robin.murphy@xxxxxxx>
> Cc: Ada Couprie Diaz <ada.coupriediaz@xxxxxxx>
> Cc: Ard Biesheuvel <ardb@xxxxxxxxxx>
> Cc: Marc Zyngier <maz@xxxxxxxxxx>
> Cc: Anshuman Khandual <anshuman.khandual@xxxxxxx>
> Cc: Ryan Roberts <ryan.roberts@xxxxxxx>
> Cc: Suren Baghdasaryan <surenb@xxxxxxxxxx>
> Cc: Tangquan Zheng <zhengtangquan@xxxxxxxx>
> Signed-off-by: Barry Song <baohua@xxxxxxxxxx>
> ---
>  kernel/dma/direct.c | 14 +++++++-------
>  1 file changed, 7 insertions(+), 7 deletions(-)

<...>

> -             if (!dev_is_dma_coherent(dev)) {
> +             if (!dev_is_dma_coherent(dev))
>                       arch_sync_dma_for_device(paddr, sg->length,
>                                       dir);
> -                     arch_sync_dma_flush();
> -             }
>       }
> +     if (!dev_is_dma_coherent(dev))
> +             arch_sync_dma_flush();

This patch should be squashed into the previous one. You introduced
arch_sync_dma_flush() there, and now you are placing it elsewhere.

Thanks