Re: [PATCH V2 10/10] iommu/arm: Remove code duplication in all IOMMU drivers

[Julien Grall <julien@xxxxxxx>]

Hi,

On 20/12/2021 21:15, Oleksandr Tyshchenko wrote:
> From: Oleksandr Tyshchenko <oleksandr_tyshchenko@xxxxxxxx>
>
> All IOMMU drivers on Arm perform almost the same generic actions in
> hwdom_init callback. Move this code to common arch_iommu_hwdom_init()
> in order to get rid of code duplication.
>
> Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@xxxxxxxx>
> Reviewed-by: Volodymyr Babchuk <volodymyr_babchuk@xxxxxxxx>
> Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
> ---
> Changes V1 -> V2:
>     - add R-b
> ---
>   xen/drivers/passthrough/arm/iommu.c      |  7 +++++++
>   xen/drivers/passthrough/arm/ipmmu-vmsa.c |  8 --------
>   xen/drivers/passthrough/arm/smmu-v3.c    | 10 ----------
>   xen/drivers/passthrough/arm/smmu.c       | 10 ----------
>   4 files changed, 7 insertions(+), 28 deletions(-)
>
> diff --git a/xen/drivers/passthrough/arm/iommu.c 
> b/xen/drivers/passthrough/arm/iommu.c
> index ee653a9..fc45318 100644
> --- a/xen/drivers/passthrough/arm/iommu.c
> +++ b/xen/drivers/passthrough/arm/iommu.c
> @@ -134,6 +134,13 @@ void arch_iommu_domain_destroy(struct domain *d)
>   
>   void __hwdom_init arch_iommu_hwdom_init(struct domain *d)
>   {
> +    /* Set to false options not supported on ARM. */
> +    if ( iommu_hwdom_inclusive )
> +        printk(XENLOG_WARNING "map-inclusive dom0-iommu option is not supported on 
> ARM\n");
> +    iommu_hwdom_inclusive = false;
> +    if ( iommu_hwdom_reserved == 1 )
> +        printk(XENLOG_WARNING "map-reserved dom0-iommu option is not supported on 
> ARM\n");
> +    iommu_hwdom_reserved = 0;
>   }
>   
>   /*
> diff --git a/xen/drivers/passthrough/arm/ipmmu-vmsa.c 
> b/xen/drivers/passthrough/arm/ipmmu-vmsa.c
> index 1224ea4..64d8ddc 100644
> --- a/xen/drivers/passthrough/arm/ipmmu-vmsa.c
> +++ b/xen/drivers/passthrough/arm/ipmmu-vmsa.c
> @@ -1325,14 +1325,6 @@ static int ipmmu_iommu_domain_init(struct domain *d)
>   
>   static void __hwdom_init ipmmu_iommu_hwdom_init(struct domain *d)
>   {
> -    /* Set to false options not supported on ARM. */
> -    if ( iommu_hwdom_inclusive )
> -        printk(XENLOG_WARNING "ipmmu: map-inclusive dom0-iommu option is not 
> supported on ARM\n");
> -    iommu_hwdom_inclusive = false;
> -    if ( iommu_hwdom_reserved == 1 )
> -        printk(XENLOG_WARNING "ipmmu: map-reserved dom0-iommu option is not 
> supported on ARM\n");
> -    iommu_hwdom_reserved = 0;
> -
>       arch_iommu_hwdom_init(d);
>   }
With this change, ipmmu_iommu_domain_init() is just a call to 
arch_iommu_hwdom_init(). The two functions have the same prototype, so 
could we simply drop the former and update the .hwdom_init to directly 
point to the latter?
>   
> diff --git a/xen/drivers/passthrough/arm/smmu-v3.c b/xen/drivers/passthrough/arm/smmu-v3.c
> index d115df7..ca8b5c7 100644
> --- a/xen/drivers/passthrough/arm/smmu-v3.c
> +++ b/xen/drivers/passthrough/arm/smmu-v3.c
> @@ -3404,16 +3404,6 @@ static int arm_smmu_iommu_xen_domain_init(struct domain 
> *d)
>   
>   static void __hwdom_init arm_smmu_iommu_hwdom_init(struct domain *d)
>   {
> -       /* Set to false options not supported on ARM. */
> -       if (iommu_hwdom_inclusive)
> -               printk(XENLOG_WARNING
> -               "map-inclusive dom0-iommu option is not supported on ARM\n");
> -       iommu_hwdom_inclusive = false;
> -       if (iommu_hwdom_reserved == 1)
> -               printk(XENLOG_WARNING
> -               "map-reserved dom0-iommu option is not supported on ARM\n");
> -       iommu_hwdom_reserved = 0;
> -
>         arch_iommu_hwdom_init(d);
>   }
>   
Same here.

> diff --git a/xen/drivers/passthrough/arm/smmu.c 
> b/xen/drivers/passthrough/arm/smmu.c
> index c9dfc4c..ec18df7 100644
> --- a/xen/drivers/passthrough/arm/smmu.c
> +++ b/xen/drivers/passthrough/arm/smmu.c
> @@ -2851,16 +2851,6 @@ static int arm_smmu_iommu_domain_init(struct domain *d)
>   
>   static void __hwdom_init arm_smmu_iommu_hwdom_init(struct domain *d)
>   {
> -       /* Set to false options not supported on ARM. */
> -       if ( iommu_hwdom_inclusive )
> -               printk(XENLOG_WARNING
> -               "map-inclusive dom0-iommu option is not supported on ARM\n");
> -       iommu_hwdom_inclusive = false;
> -       if ( iommu_hwdom_reserved == 1 )
> -               printk(XENLOG_WARNING
> -               "map-reserved dom0-iommu option is not supported on ARM\n");
> -       iommu_hwdom_reserved = 0;
> -
>         arch_iommu_hwdom_init(d);
>   }
>   
Same here.

Cheers,

--
Julien Grall