kunit: introduce kunit_kmalloc_array/kunit_kcalloc() helpers

Add in:
* kunit_kmalloc_array() and wire up kunit_kmalloc() to be a special
case of it.
* kunit_kcalloc() for symmetry with kunit_kzalloc()

This should using KUnit more natural by making it more similar to the
existing *alloc() APIs.

And while we shouldn't necessarily be writing unit tests where overflow
should be a concern, it can't hurt to be safe.

Signed-off-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

include/kunit/test.h

@@ -576,17 +576,31 @@ static inline int kunit_destroy_named_resource(struct kunit *test,
  */
 void kunit_remove_resource(struct kunit *test, struct kunit_resource *res);
 
+/**
+ * kunit_kmalloc_array() - Like kmalloc_array() except the allocation is *test managed*.
+ * @test: The test context object.
+ * @n: number of elements.
+ * @size: The size in bytes of the desired memory.
+ * @gfp: flags passed to underlying kmalloc().
+ *
+ * Just like `kmalloc_array(...)`, except the allocation is managed by the test case
+ * and is automatically cleaned up after the test case concludes. See &struct
+ * kunit_resource for more information.
+ */
+void *kunit_kmalloc_array(struct kunit *test, size_t n, size_t size, gfp_t flags);
+
 /**
  * kunit_kmalloc() - Like kmalloc() except the allocation is *test managed*.
  * @test: The test context object.
  * @size: The size in bytes of the desired memory.
  * @gfp: flags passed to underlying kmalloc().
  *
- * Just like `kmalloc(...)`, except the allocation is managed by the test case
- * and is automatically cleaned up after the test case concludes. See &struct
- * kunit_resource for more information.
+ * See kmalloc() and kunit_kmalloc_array() for more information.
  */
-void *kunit_kmalloc(struct kunit *test, size_t size, gfp_t gfp);
+static inline void *kunit_kmalloc(struct kunit *test, size_t size, gfp_t gfp)
+{
+	return kunit_kmalloc_array(test, 1, size, gfp);
+}
 
 /**
  * kunit_kfree() - Like kfree except for allocations managed by KUnit.
@@ -601,13 +615,27 @@ void kunit_kfree(struct kunit *test, const void *ptr);
  * @size: The size in bytes of the desired memory.
  * @gfp: flags passed to underlying kmalloc().
  *
- * See kzalloc() and kunit_kmalloc() for more information.
+ * See kzalloc() and kunit_kmalloc_array() for more information.
  */
 static inline void *kunit_kzalloc(struct kunit *test, size_t size, gfp_t gfp)
 {
 	return kunit_kmalloc(test, size, gfp | __GFP_ZERO);
 }
 
+/**
+ * kunit_kcalloc() - Just like kunit_kmalloc_array(), but zeroes the allocation.
+ * @test: The test context object.
+ * @n: number of elements.
+ * @size: The size in bytes of the desired memory.
+ * @gfp: flags passed to underlying kmalloc().
+ *
+ * See kcalloc() and kunit_kmalloc_array() for more information.
+ */
+static inline void *kunit_kcalloc(struct kunit *test, size_t n, size_t size, gfp_t flags)
+{
+	return kunit_kmalloc_array(test, n, size, flags | __GFP_ZERO);
+}
+
 void kunit_cleanup(struct kunit *test);
 
 void __printf(2, 3) kunit_log_append(char *log, const char *fmt, ...);

lib/kunit/test.c

@@ -572,41 +572,43 @@ int kunit_destroy_resource(struct kunit *test, kunit_resource_match_t match,
 }
 EXPORT_SYMBOL_GPL(kunit_destroy_resource);
 
-struct kunit_kmalloc_params {
+struct kunit_kmalloc_array_params {
+	size_t n;
 	size_t size;
 	gfp_t gfp;
 };
 
-static int kunit_kmalloc_init(struct kunit_resource *res, void *context)
+static int kunit_kmalloc_array_init(struct kunit_resource *res, void *context)
 {
-	struct kunit_kmalloc_params *params = context;
+	struct kunit_kmalloc_array_params *params = context;
 
-	res->data = kmalloc(params->size, params->gfp);
+	res->data = kmalloc_array(params->n, params->size, params->gfp);
 	if (!res->data)
 		return -ENOMEM;
 
 	return 0;
 }
 
-static void kunit_kmalloc_free(struct kunit_resource *res)
+static void kunit_kmalloc_array_free(struct kunit_resource *res)
 {
 	kfree(res->data);
 }
 
-void *kunit_kmalloc(struct kunit *test, size_t size, gfp_t gfp)
+void *kunit_kmalloc_array(struct kunit *test, size_t n, size_t size, gfp_t gfp)
 {
-	struct kunit_kmalloc_params params = {
+	struct kunit_kmalloc_array_params params = {
 		.size = size,
+		.n = n,
 		.gfp = gfp
 	};
 
 	return kunit_alloc_resource(test,
-				    kunit_kmalloc_init,
-				    kunit_kmalloc_free,
+				    kunit_kmalloc_array_init,
+				    kunit_kmalloc_array_free,
 				    gfp,
 				    &params);
 }
-EXPORT_SYMBOL_GPL(kunit_kmalloc);
+EXPORT_SYMBOL_GPL(kunit_kmalloc_array);
 
 void kunit_kfree(struct kunit *test, const void *ptr)
 {