Messages in this thread Patch in this message | | | From | Nicolin Chen <> | Subject | [PATCH v5 1/4] iommu: Add set/unset_dev_user_data ops | Date | Thu, 27 Jul 2023 14:09:40 -0700 |
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The device behind an IOMMU might be used in the user space by a VM. So, it might have some user space data. For example, a device behind an SMMU has a static stream ID. In a virtualization use case, both a host environment and a guest environment have their own Stream IDs. A link (a lookup table) between the physical Stream ID and the virtual (user) Stream ID is needed when the host handles the user cache invalidation commands.
Add a pair of new ops to allow user space to forward user_data of a device via iommufd, and a new dev_user_data_len for data structure sanity done by the iommufd core.
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com> --- include/linux/iommu.h | 13 +++++++++++++ 1 file changed, 13 insertions(+)
diff --git a/include/linux/iommu.h b/include/linux/iommu.h index e4835230d5f0..231920efab84 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -281,6 +281,15 @@ union iommu_domain_user_data { * @remove_dev_pasid: Remove any translation configurations of a specific * pasid, so that any DMA transactions with this pasid * will be blocked by the hardware. + * @set/unset_dev_user_data: set/unset an iommu specific device data from user + * space. The user device data info will be used by + * the driver to take care of user space requests. + * The device data structure must be defined in + * include/uapi/linux/iommufd.h. + * @dev_user_data_len: Length of the device data from user space (in bytes), + * simply the "sizeof" the data structure defined in the + * include/uapi/linux/iommufd.h. This is used by iommufd + * core to run a data length validation. * @hw_info_type: One of enum iommu_hw_info_type defined in * include/uapi/linux/iommufd.h. It is used to tag the type * of data returned by .hw_info callback. The drivers that @@ -326,6 +335,10 @@ struct iommu_ops { int (*def_domain_type)(struct device *dev); void (*remove_dev_pasid)(struct device *dev, ioasid_t pasid); + int (*set_dev_user_data)(struct device *dev, const void *user_data); + void (*unset_dev_user_data)(struct device *dev); + size_t dev_user_data_len; + const struct iommu_domain_ops *default_domain_ops; enum iommu_hw_info_type hw_info_type; unsigned long pgsize_bitmap; -- 2.41.0
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