kernel/linux.git/include/uapi/linux/iommufd.h, branch v6.12.80

iommufd: Extend IOMMU_GET_HW_INFO to report PASID capability

2025-05-29T09:02:04+00:00

[ Upstream commit 803f97298e7de9242eb677a1351dcafbbcc9117e ] PASID usage requires PASID support in both device and IOMMU. Since the iommu drivers always enable the PASID capability for the device if it is supported, this extends the IOMMU_GET_HW_INFO to report the PASID capability to userspace. Also, enhances the selftest accordingly. Link: https://patch.msgid.link/r/20250321180143.8468-5-yi.l.liu@intel.com Cc: Bjorn Helgaas Reviewed-by: Kevin Tian Reviewed-by: Jason Gunthorpe Tested-by: Zhangfei Gao #aarch64 platform Tested-by: Nicolin Chen Signed-off-by: Yi Liu Signed-off-by: Jason Gunthorpe Signed-off-by: Sasha Levin

iommufd: Fix struct iommu_hwpt_pgfault init and padding

2025-02-17T09:05:31+00:00

commit e721f619e3ec9bae08bf419c3944cf1e6966c821 upstream. The iommu_hwpt_pgfault is used to report IO page fault data to userspace, but iommufd_fault_fops_read was never zeroing its padding. This leaks the content of the kernel stack memory to userspace. Also, the iommufd uAPI requires explicit padding and use of __aligned_u64 to ensure ABI compatibility's with 32 bit. pahole result, before: struct iommu_hwpt_pgfault { __u32 flags; /* 0 4 */ __u32 dev_id; /* 4 4 */ __u32 pasid; /* 8 4 */ __u32 grpid; /* 12 4 */ __u32 perm; /* 16 4 */ /* XXX 4 bytes hole, try to pack */ __u64 addr; /* 24 8 */ __u32 length; /* 32 4 */ __u32 cookie; /* 36 4 */ /* size: 40, cachelines: 1, members: 8 */ /* sum members: 36, holes: 1, sum holes: 4 */ /* last cacheline: 40 bytes */ }; pahole result, after: struct iommu_hwpt_pgfault { __u32 flags; /* 0 4 */ __u32 dev_id; /* 4 4 */ __u32 pasid; /* 8 4 */ __u32 grpid; /* 12 4 */ __u32 perm; /* 16 4 */ __u32 __reserved; /* 20 4 */ __u64 addr __attribute__((__aligned__(8))); /* 24 8 */ __u32 length; /* 32 4 */ __u32 cookie; /* 36 4 */ /* size: 40, cachelines: 1, members: 9 */ /* forced alignments: 1 */ /* last cacheline: 40 bytes */ } __attribute__((__aligned__(8))); Fixes: c714f15860fc ("iommufd: Add fault and response message definitions") Link: https://patch.msgid.link/r/20250120195051.2450-1-nicolinc@nvidia.com Cc: stable@vger.kernel.org Reviewed-by: Jason Gunthorpe Signed-off-by: Nicolin Chen Reviewed-by: Kevin Tian Signed-off-by: Jason Gunthorpe Signed-off-by: Greg Kroah-Hartman

iommufd: Reorder include files

2024-08-26T15:02:03+00:00

Reorder include files to alphabetic order to simplify maintenance, and separate local headers and global headers with a blank line. No functional change intended. Link: https://patch.msgid.link/r/7524b037cc05afe19db3c18f863253e1d1554fa2.1722644866.git.nicolinc@nvidia.com Signed-off-by: Nicolin Chen Signed-off-by: Jason Gunthorpe

iommufd: Put constants for all the uAPI enums

2024-07-15T12:44:54+00:00

Relying on position in the enum makes it subtly harder when doing merge resolutions or backporting as it is easy to grab a patch and not notice it is a uAPI change with a differently ordered enum. This may become a bigger problem in next cycles when iommu_hwpt_invalidate_data_type and other per-driver enums have patches flowing through different trees. So lets start including constants for all the uAPI enums to make this safer. No functional change. Link: https://lore.kernel.org/r/0-v1-2c06ec044924+133-iommufd_uapi_const_jgg@nvidia.com Reviewed-by: Kevin Tian Reviewed-by: Yi Liu Tested-by: Yi Liu Signed-off-by: Jason Gunthorpe

iommufd: Remove IOMMUFD_PAGE_RESP_FAILURE

2024-07-11T23:38:09+00:00

The response code of IOMMUFD_PAGE_RESP_FAILURE was defined to be equivalent to the "Response Failure" in PCI spec, section 10.4.2.1. This response code indicates that one or more pages within the associated request group have encountered or caused an unrecoverable error. Therefore, this response disables the PRI at the function. Modern I/O virtualization technologies, like SR-IOV, share PRI among the assignable device units. Therefore, a response failure on one unit might cause I/O failure on other units. Remove this response code so that user space can only respond with SUCCESS or INVALID. The VMM is recommended to emulate a failure response as a PRI reset, or PRI disable and changing to a non-PRI domain. Fixes: c714f15860fc ("iommufd: Add fault and response message definitions") Link: https://lore.kernel.org/r/20240710083341.44617-2-baolu.lu@linux.intel.com Signed-off-by: Lu Baolu Reviewed-by: Kevin Tian Signed-off-by: Jason Gunthorpe

iommufd: Associate fault object with iommufd_hw_pgtable

2024-07-09T16:54:32+00:00

When allocating a user iommufd_hw_pagetable, the user space is allowed to associate a fault object with the hw_pagetable by specifying the fault object ID in the page table allocation data and setting the IOMMU_HWPT_FAULT_ID_VALID flag bit. On a successful return of hwpt allocation, the user can retrieve and respond to page faults by reading and writing the file interface of the fault object. Once a fault object has been associated with a hwpt, the hwpt is iopf-capable, indicated by hwpt->fault is non NULL. Attaching, detaching, or replacing an iopf-capable hwpt to an RID or PASID will differ from those that are not iopf-capable. Link: https://lore.kernel.org/r/20240702063444.105814-9-baolu.lu@linux.intel.com Signed-off-by: Lu Baolu Reviewed-by: Kevin Tian Signed-off-by: Jason Gunthorpe

iommufd: Add iommufd fault object

2024-07-09T16:54:32+00:00

An iommufd fault object provides an interface for delivering I/O page faults to user space. These objects are created and destroyed by user space, and they can be associated with or dissociated from hardware page table objects during page table allocation or destruction. User space interacts with the fault object through a file interface. This interface offers a straightforward and efficient way for user space to handle page faults. It allows user space to read fault messages sequentially and respond to them by writing to the same file. The file interface supports reading messages in poll mode, so it's recommended that user space applications use io_uring to enhance read and write efficiency. A fault object can be associated with any iopf-capable iommufd_hw_pgtable during the pgtable's allocation. All I/O page faults triggered by devices when accessing the I/O addresses of an iommufd_hw_pgtable are routed through the fault object to user space. Similarly, user space's responses to these page faults are routed back to the iommu device driver through the same fault object. Link: https://lore.kernel.org/r/20240702063444.105814-7-baolu.lu@linux.intel.com Signed-off-by: Lu Baolu Reviewed-by: Jason Gunthorpe Reviewed-by: Kevin Tian Signed-off-by: Jason Gunthorpe

iommufd: Add fault and response message definitions

2024-07-09T16:54:32+00:00

iommu_hwpt_pgfaults represent fault messages that the userspace can retrieve. Multiple iommu_hwpt_pgfaults might be put in an iopf group, with the IOMMU_PGFAULT_FLAGS_LAST_PAGE flag set only for the last iommu_hwpt_pgfault. An iommu_hwpt_page_response is a response message that the userspace should send to the kernel after finishing handling a group of fault messages. The @dev_id, @pasid, and @grpid fields in the message identify an outstanding iopf group for a device. The @cookie field, which matches the cookie field of the last fault in the group, will be used by the kernel to look up the pending message. Link: https://lore.kernel.org/r/20240702063444.105814-6-baolu.lu@linux.intel.com Signed-off-by: Lu Baolu Reviewed-by: Kevin Tian Signed-off-by: Jason Gunthorpe

iommufd: Add data structure for Intel VT-d stage-1 cache invalidation

2024-01-11T17:01:25+00:00

This adds the data structure invalidating caches for the nested domain allocated with IOMMU_HWPT_DATA_VTD_S1 type. Link: https://lore.kernel.org/r/20240111041015.47920-8-yi.l.liu@intel.com Reviewed-by: Kevin Tian Signed-off-by: Lu Baolu Signed-off-by: Yi Liu Signed-off-by: Jason Gunthorpe

iommufd: Add IOMMU_HWPT_INVALIDATE

2024-01-11T16:55:04+00:00

In nested translation, the stage-1 page table is user-managed but cached by the IOMMU hardware, so an update on present page table entries in the stage-1 page table should be followed with a cache invalidation. Add an IOMMU_HWPT_INVALIDATE ioctl to support such a cache invalidation. It takes hwpt_id to specify the iommu_domain, and a multi-entry array to support multiple invalidation data in one ioctl. enum iommu_hwpt_invalidate_data_type is defined to tag the data type of the entries in the multi-entry array. Link: https://lore.kernel.org/r/20240111041015.47920-3-yi.l.liu@intel.com Reviewed-by: Kevin Tian Co-developed-by: Nicolin Chen Signed-off-by: Nicolin Chen Signed-off-by: Yi Liu Signed-off-by: Jason Gunthorpe