Lu Baolu says:
====================
This series implements the functionality of delivering IO page faults to
user space through the IOMMUFD framework. One feasible use case is the
nested translation. Nested translation is a hardware feature that supports
two-stage translation tables for IOMMU. The second-stage translation table
is managed by the host VMM, while the first-stage translation table is
owned by user space. This allows user space to control the IOMMU mappings
for its devices.
When an IO page fault occurs on the first-stage translation table, the
IOMMU hardware can deliver the page fault to user space through the
IOMMUFD framework. User space can then handle the page fault and respond
to the device top-down through the IOMMUFD. This allows user space to
implement its own IO page fault handling policies.
User space application that is capable of handling IO page faults should
allocate a fault object, and bind the fault object to any domain that it
is willing to handle the fault generatd for them. On a successful return
of fault object allocation, the user can retrieve and respond to page
faults by reading or writing to the file descriptor (FD) returned.
The iommu selftest framework has been updated to test the IO page fault
delivery and response functionality.
====================
* iommufd_pri:
iommufd/selftest: Add coverage for IOPF test
iommufd/selftest: Add IOPF support for mock device
iommufd: Associate fault object with iommufd_hw_pgtable
iommufd: Fault-capable hwpt attach/detach/replace
iommufd: Add iommufd fault object
iommufd: Add fault and response message definitions
iommu: Extend domain attach group with handle support
iommu: Add attach handle to struct iopf_group
iommu: Remove sva handle list
iommu: Introduce domain attachment handle
Link: https://lore.kernel.org/all/20240702063444.105814-1-baolu.lu@linux.intel.com
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Extend the selftest tool to add coverage of testing IOPF handling. This
would include the following tests:
- Allocating and destroying an iommufd fault object.
- Allocating and destroying an IOPF-capable HWPT.
- Attaching/detaching/replacing an IOPF-capable HWPT on a device.
- Triggering an IOPF on the mock device.
- Retrieving and responding to the IOPF through the file interface.
Link: https://lore.kernel.org/r/20240702063444.105814-11-baolu.lu@linux.intel.com
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
With 64k base pages, the first 128k iova length test requires less than a
byte for a bitmap, exposing a bug in the tests that assume that bitmaps are
at least a byte.
Rather than dealing with bytes, have _test_mock_dirty_bitmaps() pass the
number of bits. The caller functions are adjusted to also use bits as well,
and converting to bytes when clearing, allocating and freeing the bitmap.
Link: https://lore.kernel.org/r/20240627110105.62325-2-joao.m.martins@oracle.com
Reported-by: Matt Ochs <mochs@nvidia.com>
Fixes: a9af47e382 ("iommufd/selftest: Test IOMMU_HWPT_GET_DIRTY_BITMAP")
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Tested-by: Matt Ochs <mochs@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Rework the functions that test and set the bitmaps to receive a new
parameter (the pte_page_size) that reflects the expected PTE size in the
page tables. The same scheme is still used i.e. even bits are dirty and
odd page indexes aren't dirty. Here it just refactors to consider the size
of the PTE rather than hardcoded to IOMMU mock base page assumptions.
While at it, refactor dirty bitmap tests to use the idev_id created by the
fixture instead of creating a new one.
This is in preparation for doing tests with IOMMU hugepages where multiple
bits set as part of recording a whole hugepage as dirty and thus the
pte_page_size will vary depending on io hugepages or io base pages.
Link: https://lore.kernel.org/r/20240202133415.23819-6-joao.m.martins@oracle.com
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
The ASSERT_EQ() macro sneakily expands to two statements, so the loop here
needs braces to ensure it captures both and actually terminates the test
upon failure. Where these tests are currently failing on my arm64 machine,
this reduces the number of logged lines from a rather unreasonable
~197,000 down to 10. While we're at it, we can also clean up the
tautologous "count" calculations whose assertions can never fail unless
mathematics and/or the C language become fundamentally broken.
Fixes: a9af47e382 ("iommufd/selftest: Test IOMMU_HWPT_GET_DIRTY_BITMAP")
Link: https://lore.kernel.org/r/90e083045243ef407dd592bb1deec89cd1f4ddf2.1700153535.git.robin.murphy@arm.com
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Tested-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Change test_mock_dirty_bitmaps() to pass a flag where it specifies the flag
under test. The test does the same thing as the GET_DIRTY_BITMAP regular
test. Except that it tests whether the dirtied bits are fetched all the
same a second time, as opposed to observing them cleared.
Link: https://lore.kernel.org/r/20231024135109.73787-19-joao.m.martins@oracle.com
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Add a new test ioctl for simulating the dirty IOVAs in the mock domain, and
implement the mock iommu domain ops that get the dirty tracking supported.
The selftest exercises the usual main workflow of:
1) Setting dirty tracking from the iommu domain
2) Read and clear dirty IOPTEs
Different fixtures will test different IOVA range sizes, that exercise
corner cases of the bitmaps.
Link: https://lore.kernel.org/r/20231024135109.73787-17-joao.m.martins@oracle.com
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Expand mock_domain test to be able to manipulate the device capabilities.
This allows testing with mockdev without dirty tracking support advertised
and thus make sure enforce_dirty test does the expected.
To avoid breaking IOMMUFD_TEST UABI replicate the mock_domain struct and
thus add an input dev_flags at the end.
Link: https://lore.kernel.org/r/20231024135109.73787-14-joao.m.martins@oracle.com
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Cover the essential functionality of the iommufd with a directed test from
userspace. This aims to achieve reasonable functional coverage using the
in-kernel self test framework.
A second test does a failure injection sweep of the success paths to study
error unwind behaviors.
This allows achieving high coverage of the corner cases in pages.c.
The selftest requires CONFIG_IOMMUFD_TEST to be enabled, and several huge
pages which may require:
echo 4 > /proc/sys/vm/nr_hugepages
Link: https://lore.kernel.org/r/19-v6-a196d26f289e+11787-iommufd_jgg@nvidia.com
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Matthew Rosato <mjrosato@linux.ibm.com> # s390
Tested-by: Yi Liu <yi.l.liu@intel.com>
Tested-by: Eric Auger <eric.auger@redhat.com> # aarch64
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
