Re: [PATCH v4 07/28] iommu/arm-smmu-v3: Move TLB range invalidation into a macro

[Will Deacon <will@kernel.org>]

On Tue, Aug 19, 2025 at 09:51:35PM +0000, Mostafa Saleh wrote:
> diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
> index 2698438cd35c..a222fb7ef2ec 100644
> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
> @@ -1042,6 +1042,70 @@ static inline void arm_smmu_write_strtab_l1_desc(struct arm_smmu_strtab_l1 *dst,
>  	WRITE_ONCE(dst->l2ptr, cpu_to_le64(val));
>  }
>  
> +/**
> + * arm_smmu_tlb_inv_build - Create a range invalidation command
> + * @cmd: Base command initialized with OPCODE (S1, S2..), vmid and asid.
> + * @iova: Start IOVA to invalidate
> + * @size: Size of range
> + * @granule: Granule of invalidation
> + * @pgsize_bitmap: Page size bit map of the page table.
> + * @smmu: Struct for the smmu, must have ::features
> + * @add_cmd: Function to send/batch the invalidation command
> + * @cmds: Incase of batching, it includes the pointer to the batch
> + */
> +#define arm_smmu_tlb_inv_build(cmd, iova, size, granule, pgsize_bitmap, smmu, add_cmd, cmds) \
> +{ \
> +	unsigned long _iova = (iova);						\
> +	size_t _size = (size);							\
> +	size_t _granule = (granule);						\
> +	unsigned long end = _iova + _size, num_pages = 0, tg = 0;		\
> +	size_t inv_range = _granule;						\

This is pretty gross and I've been (very sporadically) trying to replace
the similar macro we have on the CPU side with static inline functions
instead.

Can you use an inline function here too?

Will