[PATCH 04/22] iommu/amd: Introduce IOMMUFD vIOMMU support for AMD

Suravee Suthikulpanit
2026-03-30T08:43:03Z

Introduce a new enum iommu_viommu_type (IOMMU_VIOMMU_TYPE_AMD) for AMD
vIOMMU along with the struct iommu_viommu_amd, which is used to initialize
IOMMUFD vIOMMU instance when calling struct iommu_ops.viommu_init().

Also, hook up struct iomufd_viomu_ops.alloc_domain_nested to connect
nested domain allocation with AMD vIOMMU implementation.

Additional initialization will be added in subsequent patches.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
---
drivers/iommu/amd/iommufd.c | 4 ++++
include/uapi/linux/iommufd.h | 10 ++++++++++
2 files changed, 14 insertions(+)

diff --git a/drivers/iommu/amd/iommufd.c b/drivers/iommu/amd/iommufd.c
index ad627fd5ccc7..e7ffa7e8915b 100644
--- a/drivers/iommu/amd/iommufd.c
+++ b/drivers/iommu/amd/iommufd.c
@@ -34,6 +34,9 @@ void *amd_iommufd_hw_info(struct device *dev, u32 *length, u32 *type)

size_t amd_iommufd_get_viommu_size(struct device *dev, enum iommu_viommu_type viommu_type)
{
+ if (viommu_type != IOMMU_VIOMMU_TYPE_AMD)
+ return 0;
+
return VIOMMU_STRUCT_SIZE(struct amd_iommu_viommu, core);
}

@@ -73,5 +76,6 @@ static void amd_iommufd_viommu_destroy(struct iommufd_viommu *viommu)
* struct iommufd_viommu_ops - vIOMMU specific operations
*/
static const struct iommufd_viommu_ops amd_viommu_ops = {
+ .alloc_domain_nested = amd_iommu_alloc_domain_nested,
.destroy = amd_iommufd_viommu_destroy,
};
diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h
index 1dafbc552d37..3a2ac7234b9e 100644
--- a/include/uapi/linux/iommufd.h
+++ b/include/uapi/linux/iommufd.h
@@ -1048,11 +1048,13 @@ struct iommu_fault_alloc {
* @IOMMU_VIOMMU_TYPE_ARM_SMMUV3: ARM SMMUv3 driver specific type
* @IOMMU_VIOMMU_TYPE_TEGRA241_CMDQV: NVIDIA Tegra241 CMDQV (extension for ARM
* SMMUv3) enabled ARM SMMUv3 type
+ * @IOMMU_VIOMMU_TYPE_AMD: AMD HW-vIOMMU type
*/
enum iommu_viommu_type {
IOMMU_VIOMMU_TYPE_DEFAULT = 0,
IOMMU_VIOMMU_TYPE_ARM_SMMUV3 = 1,
IOMMU_VIOMMU_TYPE_TEGRA241_CMDQV = 2,
+ IOMMU_VIOMMU_TYPE_AMD = 3,
};

/**
@@ -1071,6 +1073,14 @@ struct iommu_viommu_tegra241_cmdqv {
__aligned_u64 out_vintf_mmap_length;
};

+/**
+ * struct iommu_viommu_amd - AMD vIOMMU Interface (IOMMU_VIOMMU_TYPE_AMD)
+ * @reserved: Must be zero
+ */
+struct iommu_viommu_amd {
+ __u32 reserved; /* must be last */
+};
+
/**
* struct iommu_viommu_alloc - ioctl(IOMMU_VIOMMU_ALLOC)
* @size: sizeof(struct iommu_viommu_alloc)
--
2.34.1