On Mon, Apr 28, 2025 at 10:19:21AM -0700, Nicolin Chen wrote:
On Sun, Apr 27, 2025 at 02:31:54PM +0800, Baolu Lu wrote:
On 4/26/25 13:57, Nicolin Chen wrote:
The new type of vIOMMU for tegra241-cmdqv needs to pass in a driver-level data structure from user space via iommufd, so add a user_data to the op.
Reviewed-by: Jason Gunthorpejgg@nvidia.com Signed-off-by: Nicolin Chennicolinc@nvidia.com
It would be better to add some words explaining what kind of user data can be passed when allocating a vIOMMU object and the reason why this might be necessary.
Reviewed-by: Lu Baolu baolu.lu@linux.intel.com
Sure. Will do something like this:
The new type of vIOMMU for tegra241-cmdqv allows user space VM to use one of its virtual command queue HW resources exclusively. This requires user space to mmap the corresponding MMIO page from kernel space for direct HW control.
To forward the mmap info (vm_pgoff and size), iommufd should add a driver specific data structure to the IOMMUFD_CMD_VIOMMU_ALLOC ioctl, for driver to output the info (during the allocation) back to user space.
Similar to the existing ioctls and their IOMMU handlers, add a user_data to viommu_alloc op to bridge between iommufd and drivers.
Ack, with this change (addressing Lu's nit).
Reviewed-by: Pranjal Shrivastava praan@google.com
Thanks Nicolin