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

From: Yi Liu
Date: Sun Jul 31 2022 - 08:38:29 EST


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@xxxxxxxxx>

Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
Reviewed-by: Jean-Philippe Brucker <jean-philippe@xxxxxxxxxx>
Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>
Tested-by: Zhangfei Gao <zhangfei.gao@xxxxxxxxxx>
Tested-by: Tony Zhu <tony.zhu@xxxxxxxxx>
---
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