Re: [PATCH v9 7/7] xen/asm-generic: fold struct devarch into struct dev

[Jan Beulich <jbeulich@xxxxxxxx>]

On 16.02.2024 13:39, Oleksii Kurochko wrote:
> The current patch is a follow-up to the patch titled:
>     xen/asm-generic: introduce generic device.h
> Also, a prerequisite for this patch is, without which a compilation
> error will occur:
>     xen/arm: switch Arm to use asm-generic/device.h
> 
> The 'struct dev_archdata' is exclusively used within 'struct device',
> so it could be merged into 'struct device.'
> 
> After the merger, it is necessary to update the 'dev_archdata()'
> macros and the comments above 'struct arm_smmu_xen_device' in
> drivers/passthrough/arm/smmu.c.
> Additionally, it is required to update instances of
> "dev->archdata->iommu" to "dev->iommu".
> 
> Suggested-by: Julien Grall <julien@xxxxxxx>
> Signed-off-by: Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>
> ---
>   This patch can be merged with patches 4 and 5 of this patch series.
> ---
> Changes in V9:
>  - newly introduced patch.
> ---
>  xen/drivers/passthrough/arm/smmu.c | 12 ++++++------
>  xen/include/asm-generic/device.h   |  8 +-------
>  2 files changed, 7 insertions(+), 13 deletions(-)
> 
> diff --git a/xen/drivers/passthrough/arm/smmu.c 
> b/xen/drivers/passthrough/arm/smmu.c
> index 32e2ff279b..4a272c8779 100644
> --- a/xen/drivers/passthrough/arm/smmu.c
> +++ b/xen/drivers/passthrough/arm/smmu.c
> @@ -227,9 +227,9 @@ struct arm_smmu_xen_domain {
>  };
>  
>  /*
> - * Xen: Information about each device stored in dev->archdata.iommu
> + * Xen: Information about each device stored in dev->iommu
>   *
> - * Initially dev->archdata.iommu only stores the iommu_domain (runtime
> + * Initially dev->iommu only stores the iommu_domain (runtime
>   * configuration of the SMMU) but, on Xen, we also have to store the
>   * iommu_group (list of streamIDs associated to the device).
>   *
> @@ -242,7 +242,7 @@ struct arm_smmu_xen_device {
>       struct iommu_group *group;
>  };
>  
> -#define dev_archdata(dev) ((struct arm_smmu_xen_device *)dev->archdata.iommu)
> +#define dev_archdata(dev) ((struct arm_smmu_xen_device *)dev->iommu)

I find in particular the naming here odd. But I'll let Julien judge whether
this really is along the lines of what he suggested.

Jan