Hi Eric,
On 2025/12/11 02:43, Eric Auger wrote:
On 12/5/25 12:53 AM, Pierrick Bouvier wrote:
On 11/26/25 7:45 AM, Tao Tang wrote:
Introduce qos-smmuv3, a reusable library for SMMUv3-related qtest
operations. This module encapsulates common tasks like:
- SMMUv3 initialization (enabling, configuring command/event queues)
- Stream Table Entry (STE) and Context Descriptor (CD) setup
- Multi-level page table construction (L0-L3 for 4KB granules)
- Support for Stage 1, Stage 2, and nested translation modes
- Could be easily extended to support multi-space testing infrastructure
(Non-Secure, Secure, Root, Realm)
The library provides high-level abstractions that allow test code to
focus on IOMMU behavior validation rather than low-level register
manipulation and page table encoding. Key features include:
- Automatic memory allocation for translation structures with proper
alignment
- Helper functions to build valid STEs/CDs for different translation
scenarios
- Page table walkers that handle address offset calculations per
security space
- Command queue management for SMMU configuration commands
This infrastructure is designed to be used by iommu-testdev-based tests
and future SMMUv3 test suites, reducing code duplication and improving
test maintainability.
Signed-off-by: Tao Tang <[email protected]>
---
tests/qtest/libqos/meson.build | 3 +
tests/qtest/libqos/qos-smmuv3.c | 731 ++++++++++++++++++++++++++++++++
tests/qtest/libqos/qos-smmuv3.h | 267 ++++++++++++
3 files changed, 1001 insertions(+)
create mode 100644 tests/qtest/libqos/qos-smmuv3.c
create mode 100644 tests/qtest/libqos/qos-smmuv3.h
...
+
+void qsmmu_single_translation(QSMMUTestContext *ctx)
+{
+ uint32_t config_result;
+ uint32_t dma_result;
+ bool test_passed;
+
+ /* Configure SMMU translation */
+ config_result = qsmmu_setup_and_enable_translation(ctx);
+ if (config_result != 0) {
+ g_test_message("Configuration failed: mode=%u status=0x%x",
+ ctx->config.trans_mode, config_result);
+ return;
Is that expected to silently return if we can't configure translation?
+ }
+
+ /* Trigger DMA operation */
+ dma_result = qsmmu_trigger_dma(ctx);
+ if (dma_result != 0) {
+ g_test_message("DMA failed: mode=%u result=0x%x",
+ ctx->config.trans_mode, dma_result);
+ } else {
+ g_test_message("-> DMA succeeded: mode=%u",
ctx->config.trans_mode);
+ }
+
+ /* Validate test result */
+ test_passed = qsmmu_validate_test_result(ctx);
+ g_assert_true(test_passed);
+
+ /* Clean up translation state to prepare for the next test */
+ qsmmu_cleanup_translation(ctx);
+}
+
+void qsmmu_translation_batch(const QSMMUTestConfig *configs, size_t
count,
+ QTestState *qts, QPCIDevice *dev,
+ QPCIBar bar, uint64_t smmu_base)
+{
+ for (int i = 0; i < count; i++) {
+ /* Initialize test memory */
+ qtest_memset(qts, configs[i].dma_iova, 0x00,
configs[i].dma_len);
+ /* Execute each test configuration */
+ QSMMUTestContext ctx = {
+ .qts = qts,
+ .dev = dev,
+ .bar = bar,
+ .smmu_base = smmu_base,
+ .config = configs[i],
+ .trans_status = 0,
+ .dma_result = 0,
+ .sid = dev->devfn,
+ .tx_space = qsmmu_sec_sid_to_space(configs[i].sec_sid),
+ };
+
+ qsmmu_single_translation(&ctx);
+ g_test_message("--> Test %d completed: mode=%u sec_sid=%u "
+ "status=0x%x result=0x%x", i,
configs[i].trans_mode,
+ configs[i].sec_sid, ctx.trans_status,
ctx.dma_result);
+ }
+}
What is the reason for batching operations?
We are not in a performance critical scenario for running this test,
so it's probably better to have distinct calls to single_translation.
...
For the rest of the patch, which is quite consequent, congrats. It's
hard to review all the setup phase here, but knowing it works with the
current smmuv3 implementation, that's a good proof that it's working
as expected.
That's a huge amount of code indeed. I don't how much we shall review
this test lib but if it needs std review the patch needs to be split to
ease the review. Maybe qtest maintainers can give some guidelines here...
Eric
I agree that the current qos-smmuv3 patch is too big for a single
review. When implementing this library I actually spent quite some time
debugging it, especially getting the page tables right, which is part of
why it initially came as one large chunk.
I plan to split it into several smaller patches along functional boundaries:
- one for the basic structures and common helpers, then separate patches
for
- Stage-1,
- Stage-2,
- nested translation support,
- for the more complex nested case I can further split the changes if
that makes the review easier.
I would very much appreciate qtest maintainers' professional advices on
the overall shape and layering of this test library before I start
splitting it up.
Best regards,
Tao
