At the moment, the SMMUv3 unit tests assume ATS is always enabled,
although this is sufficient to test hitless/non-hitless transitions,
but exercising other features is useful to check ste/cd population
logic (for example the .get_used logic).
Add an enum where bits define features per-master, at the moment there
is only ATS and STALLs which are mutually exclusive, but this would
make it easier to extend with other features in the future.
Also, Add 2 more tests for s1 <-> s2 transitions with stalls enabled.
Signed-off-by: Mostafa Saleh <smostafa@google.com>
Link: https://lore.kernel.org/r/20240830110349.797399-3-smostafa@google.com
Signed-off-by: Will Deacon <will@kernel.org>
With ARCH=arm64, make allmodconfig && make W=1 C=1 reports:
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-test.o
Add the missing invocation of the MODULE_DESCRIPTION() macro.
Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Fixes: da55da5a42 ("iommu/arm-smmu-v3: Make the kunit into a module")
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20240613-md-arm64-drivers-iommu-arm-arm-smmu-v3-v1-1-0e9f7584a5c8@quicinc.com
Signed-off-by: Will Deacon <will@kernel.org>
S1DSS brings in quite a few new transition pairs that are
interesting. Test to/from S1DSS_BYPASS <-> S1DSS_SSID0, and
BYPASS <-> S1DSS_SSID0.
Test a contrived non-hitless flow to make sure that the logic works.
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Michael Shavit <mshavit@google.com>
Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/12-v9-5cd718286059+79186-smmuv3_newapi_p2b_jgg@nvidia.com
Signed-off-by: Will Deacon <will@kernel.org>
The HW supports this, use the S1DSS bits to configure the behavior
of SSID=0 which is the RID's translation.
If SSID's are currently being used in the CD table then just update the
S1DSS bits in the STE, remove the master_domain and leave ATS alone.
For iommufd the driver design has a small problem that all the unused CD
table entries are set with V=0 which will generate an event if VFIO
userspace tries to use the CD entry. This patch extends this problem to
include the RID as well if PASID is being used.
For BLOCKED with used PASIDs the
F_STREAM_DISABLED (STRTAB_STE_1_S1DSS_TERMINATE) event is generated on
untagged traffic and a substream CD table entry with V=0 (removed pasid)
will generate C_BAD_CD. Arguably there is no advantage to using S1DSS over
the CD entry 0 with V=0.
As we don't yet support PASID in iommufd this is a problem to resolve
later, possibly by using EPD0 for unused CD table entries instead of V=0,
and not using S1DSS for BLOCKED.
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/11-v9-5cd718286059+79186-smmuv3_newapi_p2b_jgg@nvidia.com
Signed-off-by: Will Deacon <will@kernel.org>
The core code allows the domain to be changed on the fly without a forced
stop in BLOCKED/IDENTITY. In this flow the driver should just continually
maintain the ATS with no change while the STE is updated.
ATS relies on a linked list smmu_domain->devices to keep track of which
masters have the domain programmed, but this list is also used by
arm_smmu_share_asid(), unrelated to ats.
Create two new functions to encapsulate this combined logic:
arm_smmu_attach_prepare()
<caller generates and sets the STE>
arm_smmu_attach_commit()
The two functions can sequence both enabling ATS and disabling across
the STE store. Have every update of the STE use this sequence.
Installing a S1/S2 domain always enables the ATS if the PCIe device
supports it.
The enable flow is now ordered differently to allow it to be hitless:
1) Add the master to the new smmu_domain->devices list
2) Program the STE
3) Enable ATS at PCIe
4) Remove the master from the old smmu_domain
This flow ensures that invalidations to either domain will generate an ATC
invalidation to the device while the STE is being switched. Thus we don't
need to turn off the ATS anymore for correctness.
The disable flow is the reverse:
1) Disable ATS at PCIe
2) Program the STE
3) Invalidate the ATC
4) Remove the master from the old smmu_domain
Move the nr_ats_masters adjustments to be close to the list
manipulations. It is a count of the number of ATS enabled masters
currently in the list. This is stricly before and after the STE/CD are
revised, and done under the list's spin_lock.
This is part of the bigger picture to allow changing the RID domain while
a PASID is in use. If a SVA PASID is relying on ATS to function then
changing the RID domain cannot just temporarily toggle ATS off without
also wrecking the SVA PASID. The new infrastructure here is organized so
that the PASID attach/detach flows will make use of it as well in
following patches.
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>
Reviewed-by: Michael Shavit <mshavit@google.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/4-v9-5cd718286059+79186-smmuv3_newapi_p2b_jgg@nvidia.com
Signed-off-by: Will Deacon <will@kernel.org>
It turns out kconfig has problems ensuring the SMMU module and the KUNIT
module are consistently y/m to allow linking. It will permit KUNIT to be a
module while SMMU is built in.
Also, Fedora apparently enables kunit on production kernels.
So, put the entire kunit in its own module using the
VISIBLE_IF_KUNIT/EXPORT_SYMBOL_IF_KUNIT machinery. This keeps it out of
vmlinus on Fedora and makes the kconfig work in the normal way. There is
no cost if kunit is disabled.
Fixes: 56e1a4cc25 ("iommu/arm-smmu-v3: Add unit tests for arm_smmu_write_entry")
Reported-by: Thorsten Leemhuis <linux@leemhuis.info>
Link: https://lore.kernel.org/all/aeea8546-5bce-4c51-b506-5d2008e52fef@leemhuis.info
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Thorsten Leemhuis <linux@leemhuis.info>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/0-v1-24cba6c0f404+2ae-smmu_kunit_module_jgg@nvidia.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Add tests for some of the more common STE update operations that we expect
to see, as well as some artificial STE updates to test the edges of
arm_smmu_write_entry. These also serve as a record of which common
operation is expected to be hitless, and how many syncs they require.
arm_smmu_write_entry implements a generic algorithm that updates an STE/CD
to any other abritrary STE/CD configuration. The update requires a
sequence of write+sync operations with some invariants that must be held
true after each sync. arm_smmu_write_entry lends itself well to
unit-testing since the function's interaction with the STE/CD is already
abstracted by input callbacks that we can hook to introspect into the
sequence of operations. We can use these hooks to guarantee that
invariants are held throughout the entire update operation.
Link: https://lore.kernel.org/r/20240106083617.1173871-3-mshavit@google.com
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Michael Shavit <mshavit@google.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/9-v9-5040dc602008+177d7-smmuv3_newapi_p2_jgg@nvidia.com
Signed-off-by: Will Deacon <will@kernel.org>
