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Message-ID: <532a9259-a1f4-dc1e-acfe-8ac2c6de71b9@linux.intel.com>
Date:   Fri, 11 Feb 2022 09:33:20 +0800
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Cc:     baolu.lu@linux.intel.com, iommu@lists.linux-foundation.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] iommu: Remove trivial ops->capable implementations
Content-Language: en-US
To:     Robin Murphy <robin.murphy@arm.com>, joro@8bytes.org,
        will@kernel.org
References: <8413578c6f8a7cf75530b00cba8f10f5b88f8517.1644495614.git.robin.murphy@arm.com>
From:   Lu Baolu <baolu.lu@linux.intel.com>
In-Reply-To: <8413578c6f8a7cf75530b00cba8f10f5b88f8517.1644495614.git.robin.murphy@arm.com>
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On 2/10/22 8:29 PM, Robin Murphy wrote:
> Implementing ops->capable to always return false is pointless since it's
> the default behaviour anyway. Clean up the unnecessary implementations.
> 
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
> ---
> 
> Spinning this out of my bus ops stuff (currently 30 patches and
> counting...) since it would be better off alongside Baolu's cleanup
> series to avoid conflicts, and I want to depend on those patches for
> dev_iommu_ops() anyway.
> 
>   drivers/iommu/msm_iommu.c  | 6 ------
>   drivers/iommu/tegra-gart.c | 6 ------
>   drivers/iommu/tegra-smmu.c | 6 ------
>   3 files changed, 18 deletions(-)
> 
> diff --git a/drivers/iommu/msm_iommu.c b/drivers/iommu/msm_iommu.c
> index 06bde6b66732..22061ddbd5df 100644
> --- a/drivers/iommu/msm_iommu.c
> +++ b/drivers/iommu/msm_iommu.c
> @@ -558,11 +558,6 @@ static phys_addr_t msm_iommu_iova_to_phys(struct iommu_domain *domain,
>   	return ret;
>   }
>   
> -static bool msm_iommu_capable(enum iommu_cap cap)
> -{
> -	return false;
> -}
> -
>   static void print_ctx_regs(void __iomem *base, int ctx)
>   {
>   	unsigned int fsr = GET_FSR(base, ctx);
> @@ -672,7 +667,6 @@ irqreturn_t msm_iommu_fault_handler(int irq, void *dev_id)
>   }
>   
>   static struct iommu_ops msm_iommu_ops = {
> -	.capable = msm_iommu_capable,
>   	.domain_alloc = msm_iommu_domain_alloc,
>   	.domain_free = msm_iommu_domain_free,
>   	.attach_dev = msm_iommu_attach_dev,
> diff --git a/drivers/iommu/tegra-gart.c b/drivers/iommu/tegra-gart.c
> index 6a358f92c7e5..bbd287d19324 100644
> --- a/drivers/iommu/tegra-gart.c
> +++ b/drivers/iommu/tegra-gart.c
> @@ -238,11 +238,6 @@ static phys_addr_t gart_iommu_iova_to_phys(struct iommu_domain *domain,
>   	return pte & GART_PAGE_MASK;
>   }
>   
> -static bool gart_iommu_capable(enum iommu_cap cap)
> -{
> -	return false;
> -}
> -
>   static struct iommu_device *gart_iommu_probe_device(struct device *dev)
>   {
>   	if (!dev_iommu_fwspec_get(dev))
> @@ -276,7 +271,6 @@ static void gart_iommu_sync(struct iommu_domain *domain,
>   }
>   
>   static const struct iommu_ops gart_iommu_ops = {
> -	.capable	= gart_iommu_capable,
>   	.domain_alloc	= gart_iommu_domain_alloc,
>   	.domain_free	= gart_iommu_domain_free,
>   	.attach_dev	= gart_iommu_attach_dev,
> diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c
> index e900e3c46903..43df44f918a1 100644
> --- a/drivers/iommu/tegra-smmu.c
> +++ b/drivers/iommu/tegra-smmu.c
> @@ -272,11 +272,6 @@ static void tegra_smmu_free_asid(struct tegra_smmu *smmu, unsigned int id)
>   	clear_bit(id, smmu->asids);
>   }
>   
> -static bool tegra_smmu_capable(enum iommu_cap cap)
> -{
> -	return false;
> -}
> -
>   static struct iommu_domain *tegra_smmu_domain_alloc(unsigned type)
>   {
>   	struct tegra_smmu_as *as;
> @@ -967,7 +962,6 @@ static int tegra_smmu_of_xlate(struct device *dev,
>   }
>   
>   static const struct iommu_ops tegra_smmu_ops = {
> -	.capable = tegra_smmu_capable,
>   	.domain_alloc = tegra_smmu_domain_alloc,
>   	.domain_free = tegra_smmu_domain_free,
>   	.attach_dev = tegra_smmu_attach_dev,

Looks good to me.

Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>

Best regards,
baolu