[PATCH v12 12/17] arm-smmu-v3/sva: Add SVA domain support

Lu Baolu
2022-08-26T12:19:06Z

Add support for SVA domain allocation and provide an SVA-specific
iommu_domain_ops. This implementation is based on the existing SVA
code. Possible cleanup and refactoring are left for incremental
changes later.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Tested-by: Zhangfei Gao <zhangfei.gao@linaro.org>
---
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 13 ++++
.../iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c | 61 +++++++++++++++++++
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 21 ++++++-
3 files changed, 94 insertions(+), 1 deletion(-)

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 d2ba86470c42..c9544b656756 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -758,6 +758,9 @@ 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);
+void arm_smmu_sva_block_dev_pasid(struct iommu_domain *domain,
+ struct device *dev, ioasid_t id);
#else /* CONFIG_ARM_SMMU_V3_SVA */
static inline bool arm_smmu_sva_supported(struct arm_smmu_device *smmu)
{
@@ -803,5 +806,15 @@ static inline u32 arm_smmu_sva_get_pasid(struct iommu_sva *handle)
}

static inline void arm_smmu_sva_notifier_synchronize(void) {}
+
+static inline struct iommu_domain *arm_smmu_sva_domain_alloc(void)
+{
+ return NULL;
+}
+
+static inline void arm_smmu_sva_block_dev_pasid(struct iommu_domain *domain,
+ struct device *dev, ioasid_t id)
+{
+}
#endif /* CONFIG_ARM_SMMU_V3_SVA */
#endif /* _ARM_SMMU_V3_H */
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 f155d406c5d5..953ba19a1af8 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
@@ -549,3 +549,64 @@ void arm_smmu_sva_notifier_synchronize(void)
*/
mmu_notifier_synchronize();
}
+
+void arm_smmu_sva_block_dev_pasid(struct iommu_domain *domain,
+ struct device *dev, ioasid_t id)
+{
+ struct mm_struct *mm = domain->mm;
+ struct arm_smmu_bond *bond = NULL, *t;
+ struct arm_smmu_master *master = dev_iommu_priv_get(dev);
+
+ mutex_lock(&sva_lock);
+ list_for_each_entry(t, &master->bonds, list) {
+ if (t->mm == mm) {
+ bond = t;
+ break;
+ }
+ }
+
+ if (!WARN_ON(!bond) && refcount_dec_and_test(&bond->refs)) {
+ list_del(&bond->list);
+ arm_smmu_mmu_notifier_put(bond->smmu_mn);
+ kfree(bond);
+ }
+ mutex_unlock(&sva_lock);
+}
+
+static int arm_smmu_sva_set_dev_pasid(struct iommu_domain *domain,
+ struct device *dev, ioasid_t id)
+{
+ int ret = 0;
+ struct iommu_sva *handle;
+ struct mm_struct *mm = domain->mm;
+
+ mutex_lock(&sva_lock);
+ handle = __arm_smmu_sva_bind(dev, mm);
+ if (IS_ERR(handle))
+ ret = PTR_ERR(handle);
+ mutex_unlock(&sva_lock);
+
+ return ret;
+}
+
+static void arm_smmu_sva_domain_free(struct iommu_domain *domain)
+{
+ kfree(domain);
+}
+
+static const struct iommu_domain_ops arm_smmu_sva_domain_ops = {
+ .set_dev_pasid = arm_smmu_sva_set_dev_pasid,
+ .free = arm_smmu_sva_domain_free
+};
+
+struct iommu_domain *arm_smmu_sva_domain_alloc(void)
+{
+ struct iommu_domain *domain;
+
+ domain = kzalloc(sizeof(*domain), GFP_KERNEL);
+ if (!domain)
+ return NULL;
+ domain->ops = &arm_smmu_sva_domain_ops;
+
+ return domain;
+}
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 5520a9607758..a27ce693cc65 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -2015,9 +2015,25 @@ static int blocking_domain_attach_dev(struct iommu_domain *domain,
return 0;
}

+static int blocking_domain_set_dev_pasid(struct iommu_domain *_domain,
+ struct device *dev, ioasid_t pasid)
+{
+ struct iommu_domain *domain;
+
+ domain = iommu_get_domain_for_dev_pasid(dev, pasid, IOMMU_DOMAIN_SVA);
+ if (IS_ERR(domain))
+ return PTR_ERR(domain);
+
+ if (domain)
+ arm_smmu_sva_block_dev_pasid(domain, dev, pasid);
+
+ return 0;
+}
+
static struct iommu_domain blocking_domain = {
.ops = &(const struct iommu_domain_ops) {
- .attach_dev = blocking_domain_attach_dev
+ .attach_dev = blocking_domain_attach_dev,
+ .set_dev_pasid = blocking_domain_set_dev_pasid
}
};

@@ -2028,6 +2044,9 @@ static struct iommu_domain *arm_smmu_domain_alloc(unsigned type)
if (type == IOMMU_DOMAIN_BLOCKED)
return &blocking_domain;

+ if (type == IOMMU_DOMAIN_SVA)
+ return arm_smmu_sva_domain_alloc();
+
if (type != IOMMU_DOMAIN_UNMANAGED &&
type != IOMMU_DOMAIN_DMA &&
type != IOMMU_DOMAIN_DMA_FQ &&
--
2.25.1