Re: [PATCH v10 09/12] iommu: Remove SVA related callbacks from iommu ops

[Yi Liu <yi.l.liu@intel.com>]

On 2022/7/5 13:07, Lu Baolu wrote:
> These ops'es have been replaced with the dev_attach/detach_pasid domain
> ops'es. There's no need for them anymore. Remove them to avoid dead
> code.

nit. it is replaced by set/block_dev_pasid. isn't it?

Reviewed-by: Yi Liu <yi.l.liu@intel.com>

> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
> Reviewed-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
> Reviewed-by: Kevin Tian <kevin.tian@intel.com>
> Tested-by: Zhangfei Gao <zhangfei.gao@linaro.org>
> Tested-by: Tony Zhu <tony.zhu@intel.com>
> ---
>   include/linux/intel-iommu.h                   |  3 --
>   include/linux/iommu.h                         |  7 ---
>   drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h   | 16 ------
>   .../iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c   | 40 ---------------
>   drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c   |  3 --
>   drivers/iommu/intel/iommu.c                   |  3 --
>   drivers/iommu/intel/svm.c                     | 49 -------------------
>   7 files changed, 121 deletions(-)
> 
> diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h
> index 9007428a68f1..5bd19c95a926 100644
> --- a/include/linux/intel-iommu.h
> +++ b/include/linux/intel-iommu.h
> @@ -738,9 +738,6 @@ struct intel_iommu *device_to_iommu(struct device *dev, u8 *bus, u8 *devfn);
>   extern void intel_svm_check(struct intel_iommu *iommu);
>   extern int intel_svm_enable_prq(struct intel_iommu *iommu);
>   extern int intel_svm_finish_prq(struct intel_iommu *iommu);
> -struct iommu_sva *intel_svm_bind(struct device *dev, struct mm_struct *mm);
> -void intel_svm_unbind(struct iommu_sva *handle);
> -u32 intel_svm_get_pasid(struct iommu_sva *handle);
>   int intel_svm_page_response(struct device *dev, struct iommu_fault_event *evt,
>   			    struct iommu_page_response *msg);
>   struct iommu_domain *intel_svm_domain_alloc(void);
> diff --git a/include/linux/iommu.h b/include/linux/iommu.h
> index f59b0ecd3995..ae0cfca064e6 100644
> --- a/include/linux/iommu.h
> +++ b/include/linux/iommu.h
> @@ -227,9 +227,6 @@ struct iommu_iotlb_gather {
>    * @dev_has/enable/disable_feat: per device entries to check/enable/disable
>    *                               iommu specific features.
>    * @dev_feat_enabled: check enabled feature
> - * @sva_bind: Bind process address space to device
> - * @sva_unbind: Unbind process address space from device
> - * @sva_get_pasid: Get PASID associated to a SVA handle
>    * @page_response: handle page request response
>    * @def_domain_type: device default domain type, return value:
>    *		- IOMMU_DOMAIN_IDENTITY: must use an identity domain
> @@ -263,10 +260,6 @@ struct iommu_ops {
>   	int (*dev_enable_feat)(struct device *dev, enum iommu_dev_features f);
>   	int (*dev_disable_feat)(struct device *dev, enum iommu_dev_features f);
>   
> -	struct iommu_sva *(*sva_bind)(struct device *dev, struct mm_struct *mm);
> -	void (*sva_unbind)(struct iommu_sva *handle);
> -	u32 (*sva_get_pasid)(struct iommu_sva *handle);
> -
>   	int (*page_response)(struct device *dev,
>   			     struct iommu_fault_event *evt,
>   			     struct iommu_page_response *msg);
> 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 96399dd3a67a..15dd4c7e6d3a 100644
> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
> @@ -754,9 +754,6 @@ bool arm_smmu_master_sva_enabled(struct arm_smmu_master *master);
>   int arm_smmu_master_enable_sva(struct arm_smmu_master *master);
>   int arm_smmu_master_disable_sva(struct arm_smmu_master *master);
>   bool arm_smmu_master_iopf_supported(struct arm_smmu_master *master);
> -struct iommu_sva *arm_smmu_sva_bind(struct device *dev, struct mm_struct *mm);
> -void arm_smmu_sva_unbind(struct iommu_sva *handle);
> -u32 arm_smmu_sva_get_pasid(struct iommu_sva *handle);
>   void arm_smmu_sva_notifier_synchronize(void);
>   struct iommu_domain *arm_smmu_sva_domain_alloc(void);
>   #else /* CONFIG_ARM_SMMU_V3_SVA */
> @@ -790,19 +787,6 @@ static inline bool arm_smmu_master_iopf_supported(struct arm_smmu_master *master
>   	return false;
>   }
>   
> -static inline struct iommu_sva *
> -arm_smmu_sva_bind(struct device *dev, struct mm_struct *mm)
> -{
> -	return ERR_PTR(-ENODEV);
> -}
> -
> -static inline void arm_smmu_sva_unbind(struct iommu_sva *handle) {}
> -
> -static inline u32 arm_smmu_sva_get_pasid(struct iommu_sva *handle)
> -{
> -	return IOMMU_PASID_INVALID;
> -}
> -
>   static inline void arm_smmu_sva_notifier_synchronize(void) {}
>   
>   static inline struct iommu_domain *arm_smmu_sva_domain_alloc(void)
> diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c
> index fc4555dac5b4..e36c689f56c5 100644
> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c
> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c
> @@ -344,11 +344,6 @@ __arm_smmu_sva_bind(struct device *dev, struct mm_struct *mm)
>   	if (!bond)
>   		return ERR_PTR(-ENOMEM);
>   
> -	/* Allocate a PASID for this mm if necessary */
> -	ret = iommu_sva_alloc_pasid(mm, 1, (1U << master->ssid_bits) - 1);
> -	if (ret)
> -		goto err_free_bond;
> -
>   	bond->mm = mm;
>   	bond->sva.dev = dev;
>   	refcount_set(&bond->refs, 1);
> @@ -367,41 +362,6 @@ __arm_smmu_sva_bind(struct device *dev, struct mm_struct *mm)
>   	return ERR_PTR(ret);
>   }
>   
> -struct iommu_sva *arm_smmu_sva_bind(struct device *dev, struct mm_struct *mm)
> -{
> -	struct iommu_sva *handle;
> -	struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
> -	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
> -
> -	if (smmu_domain->stage != ARM_SMMU_DOMAIN_S1)
> -		return ERR_PTR(-EINVAL);
> -
> -	mutex_lock(&sva_lock);
> -	handle = __arm_smmu_sva_bind(dev, mm);
> -	mutex_unlock(&sva_lock);
> -	return handle;
> -}
> -
> -void arm_smmu_sva_unbind(struct iommu_sva *handle)
> -{
> -	struct arm_smmu_bond *bond = sva_to_bond(handle);
> -
> -	mutex_lock(&sva_lock);
> -	if (refcount_dec_and_test(&bond->refs)) {
> -		list_del(&bond->list);
> -		arm_smmu_mmu_notifier_put(bond->smmu_mn);
> -		kfree(bond);
> -	}
> -	mutex_unlock(&sva_lock);
> -}
> -
> -u32 arm_smmu_sva_get_pasid(struct iommu_sva *handle)
> -{
> -	struct arm_smmu_bond *bond = sva_to_bond(handle);
> -
> -	return bond->mm->pasid;
> -}
> -
>   bool arm_smmu_sva_supported(struct arm_smmu_device *smmu)
>   {
>   	unsigned long reg, fld;
> diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> index a30b252e2f95..8b9b78c7a67d 100644
> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> @@ -2855,9 +2855,6 @@ static struct iommu_ops arm_smmu_ops = {
>   	.dev_feat_enabled	= arm_smmu_dev_feature_enabled,
>   	.dev_enable_feat	= arm_smmu_dev_enable_feature,
>   	.dev_disable_feat	= arm_smmu_dev_disable_feature,
> -	.sva_bind		= arm_smmu_sva_bind,
> -	.sva_unbind		= arm_smmu_sva_unbind,
> -	.sva_get_pasid		= arm_smmu_sva_get_pasid,
>   	.page_response		= arm_smmu_page_response,
>   	.pgsize_bitmap		= -1UL, /* Restricted during device attach */
>   	.owner			= THIS_MODULE,
> diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
> index 993a1ce509a8..37d68eda1889 100644
> --- a/drivers/iommu/intel/iommu.c
> +++ b/drivers/iommu/intel/iommu.c
> @@ -4921,9 +4921,6 @@ const struct iommu_ops intel_iommu_ops = {
>   	.def_domain_type	= device_def_domain_type,
>   	.pgsize_bitmap		= SZ_4K,
>   #ifdef CONFIG_INTEL_IOMMU_SVM
> -	.sva_bind		= intel_svm_bind,
> -	.sva_unbind		= intel_svm_unbind,
> -	.sva_get_pasid		= intel_svm_get_pasid,
>   	.page_response		= intel_svm_page_response,
>   #endif
>   	.default_domain_ops = &(const struct iommu_domain_ops) {
> diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c
> index 7d4f9d173013..db55b06cafdf 100644
> --- a/drivers/iommu/intel/svm.c
> +++ b/drivers/iommu/intel/svm.c
> @@ -313,14 +313,6 @@ static int pasid_to_svm_sdev(struct device *dev, unsigned int pasid,
>   	return 0;
>   }
>   
> -static int intel_svm_alloc_pasid(struct device *dev, struct mm_struct *mm)
> -{
> -	ioasid_t max_pasid = dev_is_pci(dev) ?
> -			pci_max_pasids(to_pci_dev(dev)) : intel_pasid_max_id;
> -
> -	return iommu_sva_alloc_pasid(mm, PASID_MIN, max_pasid - 1);
> -}
> -
>   static struct iommu_sva *intel_svm_bind_mm(struct intel_iommu *iommu,
>   					   struct device *dev,
>   					   struct mm_struct *mm)
> @@ -809,47 +801,6 @@ static irqreturn_t prq_event_thread(int irq, void *d)
>   	return IRQ_RETVAL(handled);
>   }
>   
> -struct iommu_sva *intel_svm_bind(struct device *dev, struct mm_struct *mm)
> -{
> -	struct intel_iommu *iommu = device_to_iommu(dev, NULL, NULL);
> -	struct iommu_sva *sva;
> -	int ret;
> -
> -	mutex_lock(&pasid_mutex);
> -	ret = intel_svm_alloc_pasid(dev, mm);
> -	if (ret) {
> -		mutex_unlock(&pasid_mutex);
> -		return ERR_PTR(ret);
> -	}
> -
> -	sva = intel_svm_bind_mm(iommu, dev, mm);
> -	mutex_unlock(&pasid_mutex);
> -
> -	return sva;
> -}
> -
> -void intel_svm_unbind(struct iommu_sva *sva)
> -{
> -	struct intel_svm_dev *sdev = to_intel_svm_dev(sva);
> -
> -	mutex_lock(&pasid_mutex);
> -	intel_svm_unbind_mm(sdev->dev, sdev->pasid);
> -	mutex_unlock(&pasid_mutex);
> -}
> -
> -u32 intel_svm_get_pasid(struct iommu_sva *sva)
> -{
> -	struct intel_svm_dev *sdev;
> -	u32 pasid;
> -
> -	mutex_lock(&pasid_mutex);
> -	sdev = to_intel_svm_dev(sva);
> -	pasid = sdev->pasid;
> -	mutex_unlock(&pasid_mutex);
> -
> -	return pasid;
> -}
> -
>   int intel_svm_page_response(struct device *dev,
>   			    struct iommu_fault_event *evt,
>   			    struct iommu_page_response *msg)

-- 
Regards,
Yi Liu