The hw_info uAPI will support a bidirectional data_type field that can be used as an input field for user space to request for a specific info data.
To prepare for the uAPI update, change the iommu layer first: - Add a new IOMMU_HW_INFO_TYPE_DEFAULT as an input, for which driver can output its only (or firstly) supported type - Update the kdoc accordingly - Roll out the type validation in the existing drivers
Reviewed-by: Kevin Tian kevin.tian@intel.com Reviewed-by: Jason Gunthorpe jgg@nvidia.com Signed-off-by: Nicolin Chen nicolinc@nvidia.com --- include/linux/iommu.h | 6 ++++-- include/uapi/linux/iommufd.h | 4 +++- drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c | 4 ++++ drivers/iommu/intel/iommu.c | 4 ++++ drivers/iommu/iommufd/device.c | 3 +++ drivers/iommu/iommufd/selftest.c | 4 ++++ 6 files changed, 22 insertions(+), 3 deletions(-)
diff --git a/include/linux/iommu.h b/include/linux/iommu.h index c712669f3055..95e58ef9cea4 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -603,8 +603,10 @@ __iommu_copy_struct_to_user(const struct iommu_user_data *dst_data, * @capable: check capability * @hw_info: report iommu hardware information. The data buffer returned by this * op is allocated in the iommu driver and freed by the caller after - * use. The information type is one of enum iommu_hw_info_type defined - * in include/uapi/linux/iommufd.h. + * use. @type can input a requested type and output a supported type, + * either of which must be defined in enum iommu_hw_info_type in + * include/uapi/linux/iommufd.h. Driver should reject an unsupported + * data @type input * @domain_alloc: Do not use in new drivers * @domain_alloc_identity: allocate an IDENTITY domain. Drivers should prefer to * use identity_domain instead. This should only be used diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h index f091ea072c5f..6ad361ff9b06 100644 --- a/include/uapi/linux/iommufd.h +++ b/include/uapi/linux/iommufd.h @@ -593,13 +593,15 @@ struct iommu_hw_info_arm_smmuv3 {
/** * enum iommu_hw_info_type - IOMMU Hardware Info Types - * @IOMMU_HW_INFO_TYPE_NONE: Used by the drivers that do not report hardware + * @IOMMU_HW_INFO_TYPE_NONE: Output by the drivers that do not report hardware * info + * @IOMMU_HW_INFO_TYPE_DEFAULT: Input to request for a default type * @IOMMU_HW_INFO_TYPE_INTEL_VTD: Intel VT-d iommu info type * @IOMMU_HW_INFO_TYPE_ARM_SMMUV3: ARM SMMUv3 iommu info type */ enum iommu_hw_info_type { IOMMU_HW_INFO_TYPE_NONE = 0, + IOMMU_HW_INFO_TYPE_DEFAULT = 0, IOMMU_HW_INFO_TYPE_INTEL_VTD = 1, IOMMU_HW_INFO_TYPE_ARM_SMMUV3 = 2, }; 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 78d9597d7b86..c14f7e6b4dae 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 @@ -14,6 +14,10 @@ void *arm_smmu_hw_info(struct device *dev, u32 *length, u32 *type) u32 __iomem *base_idr; unsigned int i;
+ if (*type != IOMMU_HW_INFO_TYPE_DEFAULT && + *type != IOMMU_HW_INFO_TYPE_ARM_SMMUV3) + return ERR_PTR(-EOPNOTSUPP); + info = kzalloc(sizeof(*info), GFP_KERNEL); if (!info) return ERR_PTR(-ENOMEM); diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index 7aa3932251b2..d0de98cd2529 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -4097,6 +4097,10 @@ static void *intel_iommu_hw_info(struct device *dev, u32 *length, u32 *type) struct intel_iommu *iommu = info->iommu; struct iommu_hw_info_vtd *vtd;
+ if (*type != IOMMU_HW_INFO_TYPE_DEFAULT && + *type != IOMMU_HW_INFO_TYPE_INTEL_VTD) + return ERR_PTR(-EOPNOTSUPP); + vtd = kzalloc(sizeof(*vtd), GFP_KERNEL); if (!vtd) return ERR_PTR(-ENOMEM); diff --git a/drivers/iommu/iommufd/device.c b/drivers/iommu/iommufd/device.c index ad33f1e41a24..50f6c27fde32 100644 --- a/drivers/iommu/iommufd/device.c +++ b/drivers/iommu/iommufd/device.c @@ -1513,6 +1513,9 @@ int iommufd_get_hw_info(struct iommufd_ucmd *ucmd) cmd->__reserved[2]) return -EOPNOTSUPP;
+ /* Clear the type field since drivers don't support a random input */ + cmd->out_data_type = IOMMU_HW_INFO_TYPE_DEFAULT; + idev = iommufd_get_device(ucmd, cmd->dev_id); if (IS_ERR(idev)) return PTR_ERR(idev); diff --git a/drivers/iommu/iommufd/selftest.c b/drivers/iommu/iommufd/selftest.c index d100ba27f205..71251d9ff1da 100644 --- a/drivers/iommu/iommufd/selftest.c +++ b/drivers/iommu/iommufd/selftest.c @@ -309,6 +309,10 @@ static void *mock_domain_hw_info(struct device *dev, u32 *length, u32 *type) { struct iommu_test_hw_info *info;
+ if (*type != IOMMU_HW_INFO_TYPE_DEFAULT && + *type != IOMMU_HW_INFO_TYPE_SELFTEST) + return ERR_PTR(-EOPNOTSUPP); + info = kzalloc(sizeof(*info), GFP_KERNEL); if (!info) return ERR_PTR(-ENOMEM);