[PATCH v3 11/11] iommu/arm-smmu-v3: Add IOMMU_VIOMMU_TYPE_ARM_SMMUV3 support

[Nicolin Chen]

Add a new driver-type for ARM SMMUv3 to enum iommu_viommu_type. Implement
the viommu_alloc op with an arm_vsmmu_alloc function. As an initial step,
copy the VMID from s2_parent. A later cleanup series is required to move
the VMID allocation out of the stage-2 domain allocation routine to this.

Signed-off-by: Nicolin Chen <nicolinc@xxxxxxxxxx>
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h   | 18 ++++++++++++++
 include/uapi/linux/iommufd.h                  |  2 ++
 .../arm/arm-smmu-v3/arm-smmu-v3-iommufd.c     | 24 +++++++++++++++++++
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c   |  1 +
 4 files changed, 45 insertions(+)

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 e394943c0b4b..844d1dfdea55 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -10,6 +10,7 @@
 
 #include <linux/bitfield.h>
 #include <linux/iommu.h>
+#include <linux/iommufd.h>
 #include <linux/kernel.h>
 #include <linux/mmzone.h>
 #include <linux/sizes.h>
@@ -1005,12 +1006,22 @@ tegra241_cmdqv_probe(struct arm_smmu_device *smmu)
 }
 #endif /* CONFIG_TEGRA241_CMDQV */
 
+struct arm_vsmmu {
+	struct iommufd_viommu core;
+	struct arm_smmu_device *smmu;
+	struct arm_smmu_domain *s2_parent;
+	u16 vmid;
+};
+
 #if IS_ENABLED(CONFIG_ARM_SMMU_V3_IOMMUFD)
 void *arm_smmu_hw_info(struct device *dev, u32 *length, u32 *type);
 struct iommu_domain *
 arm_smmu_domain_alloc_nesting(struct device *dev, u32 flags,
 			      struct iommu_domain *parent,
 			      const struct iommu_user_data *user_data);
+struct iommufd_viommu *
+arm_vsmmu_alloc(struct iommu_device *iommu_dev, struct iommu_domain *parent,
+		struct iommufd_ctx *ictx, unsigned int viommu_type);
 #else
 #define arm_smmu_hw_info NULL
 static inline struct iommu_domain *
@@ -1020,6 +1031,13 @@ arm_smmu_domain_alloc_nesting(struct device *dev, u32 flags,
 {
 	return ERR_PTR(-EOPNOTSUPP);
 }
+
+static inline struct iommufd_viommu *
+arm_vsmmu_alloc(struct iommu_device *iommu_dev, struct iommu_domain *parent,
+		struct iommufd_ctx *ictx, unsigned int viommu_type)
+{
+	return ERR_PTR(-EOPNOTSUPP);
+}
 #endif /* CONFIG_ARM_SMMU_V3_IOMMUFD */
 
 #endif /* _ARM_SMMU_V3_H */
diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h
index ff8aece8212f..6ee841a8c79b 100644
--- a/include/uapi/linux/iommufd.h
+++ b/include/uapi/linux/iommufd.h
@@ -857,9 +857,11 @@ struct iommu_fault_alloc {
 /**
  * enum iommu_viommu_type - Virtual IOMMU Type
  * @IOMMU_VIOMMU_TYPE_DEFAULT: Core-managed virtual IOMMU type
+ * @IOMMU_VIOMMU_TYPE_ARM_SMMUV3: ARM SMMUv3 driver specific type
  */
 enum iommu_viommu_type {
 	IOMMU_VIOMMU_TYPE_DEFAULT = 0,
+	IOMMU_VIOMMU_TYPE_ARM_SMMUV3 = 1,
 };
 
 /**
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c
index 51260f63be94..5e235fca8f13 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c
@@ -212,3 +212,27 @@ arm_smmu_domain_alloc_nesting(struct device *dev, u32 flags,
 
 	return &nested_domain->domain;
 }
+
+struct iommufd_viommu *
+arm_vsmmu_alloc(struct iommu_device *iommu_dev, struct iommu_domain *parent,
+		struct iommufd_ctx *ictx, unsigned int viommu_type)
+{
+	struct arm_smmu_device *smmu =
+		container_of(iommu_dev, struct arm_smmu_device, iommu);
+	struct arm_smmu_domain *s2_parent = to_smmu_domain(parent);
+	struct arm_vsmmu *vsmmu;
+
+	if (viommu_type != IOMMU_VIOMMU_TYPE_ARM_SMMUV3)
+		return ERR_PTR(-EOPNOTSUPP);
+
+	vsmmu = iommufd_viommu_alloc(ictx, arm_vsmmu, core, NULL);
+	if (IS_ERR(vsmmu))
+		return ERR_CAST(vsmmu);
+
+	vsmmu->smmu = smmu;
+	vsmmu->s2_parent = s2_parent;
+	/* FIXME Move VMID allocation from the S2 domain allocation to here */
+	vsmmu->vmid = s2_parent->s2_cfg.vmid;
+
+	return &vsmmu->core;
+}
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 4b836a5e9fde..6a23e6dcd5cf 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -3541,6 +3541,7 @@ static struct iommu_ops arm_smmu_ops = {
 	.dev_disable_feat	= arm_smmu_dev_disable_feature,
 	.page_response		= arm_smmu_page_response,
 	.def_domain_type	= arm_smmu_def_domain_type,
+	.viommu_alloc		= arm_vsmmu_alloc,
 	.pgsize_bitmap		= -1UL, /* Restricted during device attach */
 	.owner			= THIS_MODULE,
 	.default_domain_ops = &(const struct iommu_domain_ops) {
-- 
2.43.0