iommufd: File descriptor, context, kconfig and makefiles

This is the basic infrastructure of a new miscdevice to hold the iommufd
IOCTL API.

It provides:
 - A miscdevice to create file descriptors to run the IOCTL interface over

 - A table based ioctl dispatch and centralized extendable pre-validation
   step

 - An xarray mapping userspace ID's to kernel objects. The design has
   multiple inter-related objects held within in a single IOMMUFD fd

 - A simple usage count to build a graph of object relations and protect
   against hostile userspace racing ioctls

The only IOCTL provided in this patch is the generic 'destroy any object
by handle' operation.

Link: https://lore.kernel.org/r/6-v6-a196d26f289e+11787-iommufd_jgg@nvidia.com
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Yi Liu <yi.l.liu@intel.com>
Tested-by: Lixiao Yang <lixiao.yang@intel.com>
Tested-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
This commit is contained in:
Jason Gunthorpe
2022-11-29 16:29:29 -04:00
parent 658234de0d
commit 2ff4bed7fe
10 changed files with 571 additions and 1 deletions

View File

@@ -105,6 +105,7 @@ Code Seq# Include File Comments
'8' all SNP8023 advanced NIC card
<mailto:mcr@solidum.com>
';' 64-7F linux/vfio.h
';' 80-FF linux/iommufd.h
'=' 00-3f uapi/linux/ptp_clock.h <mailto:richardcochran@gmail.com>
'@' 00-0F linux/radeonfb.h conflict!
'@' 00-0F drivers/video/aty/aty128fb.c conflict!