tools/testing/nvdimm: unit test acpi_nfit_ctl()

A recent flurry of bug discoveries in the nfit driver's DSM marshalling
routine has highlighted the fact that we do not have unit test coverage
for this routine. Add a self-test of acpi_nfit_ctl() routine before
probing the "nfit_test.0" device. This mocks stimulus to acpi_nfit_ctl()
and if any of the tests fail "nfit_test.0" will be unavailable causing
the rest of the tests to not run / fail.

This unit test will also be a place to land reproductions of quirky BIOS
behavior discovered in the field and ensure the kernel does not regress
against implementations it has seen in practice.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 22 insertions, 1 deletions

diff --git a/tools/testing/nvdimm/test/iomap.c b/tools/testing/nvdimm/test/iomap.c
index 3ccef732fce9..64cae1a5deff 100644
--- a/tools/testing/nvdimm/test/iomap.c
+++ b/tools/testing/nvdimm/test/iomap.c
@@ -26,14 +26,17 @@ static LIST_HEAD(iomap_head);
 
 static struct iomap_ops {
 	nfit_test_lookup_fn nfit_test_lookup;
+	nfit_test_evaluate_dsm_fn evaluate_dsm;
 	struct list_head list;
 } iomap_ops = {
 	.list = LIST_HEAD_INIT(iomap_ops.list),
 };
 
-void nfit_test_setup(nfit_test_lookup_fn lookup)
+void nfit_test_setup(nfit_test_lookup_fn lookup,
+		nfit_test_evaluate_dsm_fn evaluate)
 {
 	iomap_ops.nfit_test_lookup = lookup;
+	iomap_ops.evaluate_dsm = evaluate;
 	list_add_rcu(&iomap_ops.list, &iomap_head);
 }
 EXPORT_SYMBOL(nfit_test_setup);
@@ -367,4 +370,22 @@ acpi_status __wrap_acpi_evaluate_object(acpi_handle handle, acpi_string path,
 }
 EXPORT_SYMBOL(__wrap_acpi_evaluate_object);
 
+union acpi_object * __wrap_acpi_evaluate_dsm(acpi_handle handle, const u8 *uuid,
+		u64 rev, u64 func, union acpi_object *argv4)
+{
+	union acpi_object *obj = ERR_PTR(-ENXIO);
+	struct iomap_ops *ops;
+
+	rcu_read_lock();
+	ops = list_first_or_null_rcu(&iomap_head, typeof(*ops), list);
+	if (ops)
+		obj = ops->evaluate_dsm(handle, uuid, rev, func, argv4);
+	rcu_read_unlock();
+
+	if (IS_ERR(obj))
+		return acpi_evaluate_dsm(handle, uuid, rev, func, argv4);
+	return obj;
+}
+EXPORT_SYMBOL(__wrap_acpi_evaluate_dsm);
+
 MODULE_LICENSE("GPL v2");