Re: [RFC PATCH v2 3/3] arm64: hook up IOMMU dma_ops

[leizhen <thunder.leizhen-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>]

On 2015/2/6 22:55, Robin Murphy wrote:
> With iommu_dma_ops in place, hook them up to the configuration code, so
> IOMMU-fronted devices will get them automatically.
> 
> Signed-off-by: Robin Murphy <robin.murphy-5wv7dgnIgG8@public.gmane.org>
> ---
>  arch/arm64/Kconfig                   |  1 +
>  arch/arm64/include/asm/dma-mapping.h | 11 ++++++-----
>  arch/arm64/mm/dma-mapping.c          | 15 +++++++++++++++
>  3 files changed, 22 insertions(+), 5 deletions(-)
> 
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index b1f9a20..e2abcdc 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -66,6 +66,7 @@ config ARM64
>  	select HAVE_PERF_USER_STACK_DUMP
>  	select HAVE_RCU_TABLE_FREE
>  	select HAVE_SYSCALL_TRACEPOINTS
> +	select IOMMU_DMA if IOMMU_SUPPORT

IOMMU_SUPPORT is selected above, so "if IOMMU_SUPPORT" can be omitted.
And I suggest putting "select IOMMU_DMA" next to "select IOMMU_SUPPORT".

>  	select IRQ_DOMAIN
>  	select MODULES_USE_ELF_RELA
>  	select NO_BOOTMEM
> diff --git a/arch/arm64/include/asm/dma-mapping.h b/arch/arm64/include/asm/dma-mapping.h
> index c1b271f..5246d1a 100644
> --- a/arch/arm64/include/asm/dma-mapping.h
> +++ b/arch/arm64/include/asm/dma-mapping.h
> @@ -45,11 +45,8 @@ static inline struct dma_map_ops *get_dma_ops(struct device *dev)
>  		return __generic_dma_ops(dev);
>  }
>  
> -static inline void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
> -				      struct iommu_ops *iommu, bool coherent)
> -{
> -	dev->archdata.dma_coherent = coherent;
> -}
> +void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
> +			struct iommu_ops *iommu, bool coherent);
>  #define arch_setup_dma_ops	arch_setup_dma_ops
>  
>  /* do not use this function in a driver */
> @@ -63,6 +60,10 @@ static inline bool is_device_dma_coherent(struct device *dev)
>  #include <asm-generic/dma-mapping-common.h>
>  
>  #ifdef CONFIG_IOMMU_DMA
> +
> +void arch_teardown_dma_ops(struct device *dev);
> +#define arch_teardown_dma_ops	arch_teardown_dma_ops
> +
>  static inline struct iommu_dma_domain *get_dma_domain(struct device *dev)
>  {
>  	return dev->archdata.dma_domain;
> diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
> index 28e771c..2a30673 100644
> --- a/arch/arm64/mm/dma-mapping.c
> +++ b/arch/arm64/mm/dma-mapping.c
> @@ -752,6 +752,14 @@ static void __iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
>  	iommu_dma_release_domain(dma_domain);
>  }
>  
> +void arch_teardown_dma_ops(struct device *dev)
> +{
> +	if (dev->archdata.dma_domain) {
> +		iommu_dma_detach_device(dev);
> +		dev->archdata.dma_ops = NULL;
> +	}
> +}
> +
>  #else
>  
>  static void __iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
> @@ -759,3 +767,10 @@ static void __iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
>  { }
>  
>  #endif  /* CONFIG_IOMMU_DMA */
> +
> +void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
> +			struct iommu_ops *iommu, bool coherent)
> +{
> +	dev->archdata.dma_coherent = coherent;
> +	__iommu_setup_dma_ops(dev, dma_base, size, iommu);
> +}
>