Piecuu/linux-samsung-r9q2
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

iommufd: Add a nested HW pagetable object

Browse source 
IOMMU_HWPT_ALLOC already supports iommu_domain allocation for usersapce.
But it can only allocate a hw_pagetable that associates to a given IOAS,
i.e. only a kernel-managed hw_pagetable of IOMMUFD_OBJ_HWPT_PAGING type.

IOMMU drivers can now support user-managed hw_pagetables, for two-stage
translation use cases that require user data input from the user space.

Add a new IOMMUFD_OBJ_HWPT_NESTED type with its abort/destroy(). Pair it
with a new iommufd_hwpt_nested structure and its to_hwpt_nested() helper.
Update the to_hwpt_paging() helper, so a NESTED-type hw_pagetable can be
handled in the callers, for example iommufd_hw_pagetable_enforce_rr().

Screen the inputs including the parent PAGING-type hw_pagetable that has
a need of a new nest_parent flag in the iommufd_hwpt_paging structure.

Extend the IOMMU_HWPT_ALLOC ioctl to accept an IOMMU driver specific data
input which is tagged by the enum iommu_hwpt_data_type. Also, update the
@pt_id to accept hwpt_id too besides an ioas_id. Then, use them to allocate
a hw_pagetable of IOMMUFD_OBJ_HWPT_NESTED type using the
iommufd_hw_pagetable_alloc_nested() allocator.

Link: https://lore.kernel.org/r/20231026043938.63898-8-yi.l.liu@intel.com
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Co-developed-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
This commit is contained in:
Nicolin Chen 2023-10-25 21:39:35 -07:00 • committed by Jason Gunthorpe
parent 2bdabb8e82
commit bd529dbb66
5 changed files with 159 additions and 16 deletions
Download patch file Download diff file Expand all files Collapse all files

31
include/uapi/linux/iommufd.h
View file

@ -361,20 +361,44 @@ enum iommufd_hwpt_alloc_flags {
IOMMU_HWPT_ALLOC_DIRTY_TRACKING = 1 << 1,
};
/**
* enum iommu_hwpt_data_type - IOMMU HWPT Data Type
* @IOMMU_HWPT_DATA_NONE: no data
*/
enum iommu_hwpt_data_type {
IOMMU_HWPT_DATA_NONE,
};
/**
* struct iommu_hwpt_alloc - ioctl(IOMMU_HWPT_ALLOC)
* @size: sizeof(struct iommu_hwpt_alloc)
* @flags: Combination of enum iommufd_hwpt_alloc_flags
* @dev_id: The device to allocate this HWPT for
* @pt_id: The IOAS to connect this HWPT to
* @pt_id: The IOAS or HWPT to connect this HWPT to
* @out_hwpt_id: The ID of the new HWPT
* @__reserved: Must be 0
* @data_type: One of enum iommu_hwpt_data_type
* @data_len: Length of the type specific data
* @data_uptr: User pointer to the type specific data
*
* Explicitly allocate a hardware page table object. This is the same object
* type that is returned by iommufd_device_attach() and represents the
* underlying iommu driver's iommu_domain kernel object.
*
* A HWPT will be created with the IOVA mappings from the given IOAS.
* A kernel-managed HWPT will be created with the mappings from the given
* IOAS via the @pt_id. The @data_type for this allocation must be set to
* IOMMU_HWPT_DATA_NONE. The HWPT can be allocated as a parent HWPT for a
* nesting configuration by passing IOMMU_HWPT_ALLOC_NEST_PARENT via @flags.
*
* A user-managed nested HWPT will be created from a given parent HWPT via
* @pt_id, in which the parent HWPT must be allocated previously via the
* same ioctl from a given IOAS (@pt_id). In this case, the @data_type
* must be set to a pre-defined type corresponding to an I/O page table
* type supported by the underlying IOMMU hardware.
*
* If the @data_type is set to IOMMU_HWPT_DATA_NONE, @data_len and
* @data_uptr should be zero. Otherwise, both @data_len and @data_uptr
* must be given.
*/
struct iommu_hwpt_alloc {
__u32 size;
@ -383,6 +407,9 @@ struct iommu_hwpt_alloc {
__u32 pt_id;
__u32 out_hwpt_id;
__u32 __reserved;
__u32 data_type;
__u32 data_len;
__aligned_u64 data_uptr;
};
#define IOMMU_HWPT_ALLOC _IO(IOMMUFD_TYPE, IOMMUFD_CMD_HWPT_ALLOC)