From: Jason Gunthorpe jgg@nvidia.com Sent: Friday, March 10, 2023 8:56 AM
On Thu, Mar 09, 2023 at 12:08:59AM -0800, Yi Liu wrote:
diff --git a/include/linux/iommu.h b/include/linux/iommu.h index 3ef84ee359d2..a269bc62a31c 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -229,6 +229,7 @@ struct iommu_iotlb_gather {
after use. Return the data buffer if success, or ERR_PTR onfailure.- @domain_alloc: allocate iommu domain
- @domain_alloc_user: allocate user iommu domain
- @probe_device: Add device to iommu driver handling
- @release_device: Remove device from iommu driver handling
- @probe_finalize: Do final setup work after the device is added to an
IOMMU
@@ -266,6 +267,9 @@ struct iommu_ops {
/* Domain allocation and freeing by the iommu driver */ struct iommu_domain *(*domain_alloc)(unsigned
iommu_domain_type);
- struct iommu_domain *(*domain_alloc_user)(struct device *dev,
struct iommu_domain*parent,
const void *user_data);Since the kernel does the copy from user and manages the zero fill compat maybe this user_data have a union like Robin suggested.
But yes, this is the idea.
Ok. so it's a union like the below, and in this patch may be only an empty union can be added as the struct iommu_hwpt_intel_vtd and struct iommu_hwpt_arm_smmuv3 would be added by the vendor nesting patch series.
union iommu_hwpt_alloc_user_data { struct iommu_hwpt_intel_vtd vtd; struct iommu_hwpt_arm_smmuv3 smmuv3; };
Regards, Yi Liu