[PATCH RFC 05/11] arm-smmu-v3/sva: Add SVA domain support

Lu Baolu
2022-03-20T06:43:05Z

Add support for SVA domain allocation and provide an SVA-specific
iommu_domain_ops.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
---
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 14 ++++++
.../iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c | 45 +++++++++++++++++++
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 13 +++++-
3 files changed, 71 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 cd48590ada30..7631c00fdcbd 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -759,6 +759,10 @@ 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);
+int arm_smmu_sva_attach_dev_pasid(struct iommu_domain *domain,
+ struct device *dev, ioasid_t id);
+void arm_smmu_sva_detach_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)
{
@@ -804,5 +808,15 @@ static inline u32 arm_smmu_sva_get_pasid(struct iommu_sva *handle)
}

static inline void arm_smmu_sva_notifier_synchronize(void) {}
+
+static inline int arm_smmu_sva_attach_dev_pasid(struct iommu_domain *domain,
+ struct device *dev, ioasid_t id)
+{
+ return -ENODEV;
+}
+
+static inline void arm_smmu_sva_detach_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 22ddd05bbdcd..1e114b9dc17f 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
@@ -534,3 +534,48 @@ void arm_smmu_sva_notifier_synchronize(void)
*/
mmu_notifier_synchronize();
}
+
+int arm_smmu_sva_attach_dev_pasid(struct iommu_domain *domain,
+ struct device *dev, ioasid_t id)
+{
+ int ret = 0;
+ struct iommu_sva *handle;
+ struct mm_struct *mm = domain->sva_cookie;
+ struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+
+ if (smmu_domain->stage != ARM_SMMU_DOMAIN_S1 ||
+ domain->type != IOMMU_DOMAIN_SVA || !mm)
+ return -EINVAL;
+
+ mutex_lock(&sva_lock);
+ handle = __arm_smmu_sva_bind(dev, mm);
+ if (IS_ERR_OR_NULL(handle))
+ ret = PTR_ERR(handle);
+ mutex_unlock(&sva_lock);
+
+ return ret;
+}
+
+void arm_smmu_sva_detach_dev_pasid(struct iommu_domain *domain,
+ struct device *dev, ioasid_t id)
+{
+ struct arm_smmu_bond *bond = NULL, *t;
+ struct mm_struct *mm = domain->sva_cookie;
+ 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);
+ iommu_sva_free_pasid(bond->mm);
+ kfree(bond);
+ }
+ mutex_unlock(&sva_lock);
+}
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 8e262210b5ad..2e9d3cd30510 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -88,6 +88,8 @@ static struct arm_smmu_option_prop arm_smmu_options[] = {
{ 0, NULL},
};

+static void arm_smmu_domain_free(struct iommu_domain *domain);
+
static void parse_driver_options(struct arm_smmu_device *smmu)
{
int i = 0;
@@ -1995,6 +1997,12 @@ static bool arm_smmu_capable(enum iommu_cap cap)
}
}

+static const struct iommu_domain_ops arm_smmu_sva_domain_ops = {
+ .attach_dev_pasid = arm_smmu_sva_attach_dev_pasid,
+ .detach_dev_pasid = arm_smmu_sva_detach_dev_pasid,
+ .free = arm_smmu_domain_free,
+};
+
static struct iommu_domain *arm_smmu_domain_alloc(unsigned type)
{
struct arm_smmu_domain *smmu_domain;
@@ -2002,7 +2010,8 @@ static struct iommu_domain *arm_smmu_domain_alloc(unsigned type)
if (type != IOMMU_DOMAIN_UNMANAGED &&
type != IOMMU_DOMAIN_DMA &&
type != IOMMU_DOMAIN_DMA_FQ &&
- type != IOMMU_DOMAIN_IDENTITY)
+ type != IOMMU_DOMAIN_IDENTITY &&
+ type != IOMMU_DOMAIN_SVA)
return NULL;

/*
@@ -2018,6 +2027,8 @@ static struct iommu_domain *arm_smmu_domain_alloc(unsigned type)
INIT_LIST_HEAD(&smmu_domain->devices);
spin_lock_init(&smmu_domain->devices_lock);
INIT_LIST_HEAD(&smmu_domain->mmu_notifiers);
+ if (type == IOMMU_DOMAIN_SVA)
+ smmu_domain->domain.ops = &arm_smmu_sva_domain_ops;

return &smmu_domain->domain;
}
--
2.25.1