selftests/bpf: add checks for bpf_wq_set_callback()

We assign the callback and set everything up.
The actual tests of these callbacks will be done when bpf_wq_start() is
available.

Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>
Link: https://lore.kernel.org/r/20240420-bpf_wq-v2-14-6c986a5a741f@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 66 insertions, 0 deletions

diff --git a/tools/testing/selftests/bpf/progs/wq_failures.c b/tools/testing/selftests/bpf/progs/wq_failures.c
index db7015c7d541..4cbdb425f223 100644
--- a/tools/testing/selftests/bpf/progs/wq_failures.c
+++ b/tools/testing/selftests/bpf/progs/wq_failures.c
@@ -27,6 +27,20 @@ struct {
 	__type(value, struct elem);
 } lru SEC(".maps");
 
+/* callback for non sleepable workqueue */
+static int wq_callback(void *map, int *key, struct bpf_wq *work)
+{
+	bpf_kfunc_common_test();
+	return 0;
+}
+
+/* callback for sleepable workqueue */
+static int wq_cb_sleepable(void *map, int *key, struct bpf_wq *work)
+{
+	bpf_kfunc_call_test_sleepable();
+	return 0;
+}
+
 SEC("tc")
 /* test that bpf_wq_init takes a map as a second argument
  */
@@ -76,3 +90,55 @@ long test_wq_init_wrong_map(void *ctx)
 
 	return 0;
 }
+
+SEC("?tc")
+__log_level(2)
+__failure
+/* check that the first argument of bpf_wq_set_callback()
+ * is a correct bpf_wq pointer.
+ */
+__msg(": (85) call bpf_wq_set_callback_impl#") /* anchor message */
+__msg("arg#0 doesn't point to a map value")
+long test_wrong_wq_pointer(void *ctx)
+{
+	int key = 0;
+	struct bpf_wq *wq;
+
+	wq = bpf_map_lookup_elem(&array, &key);
+	if (!wq)
+		return 1;
+
+	if (bpf_wq_init(wq, &array, 0))
+		return 2;
+
+	if (bpf_wq_set_callback((void *)&wq, wq_callback, 0))
+		return 3;
+
+	return -22;
+}
+
+SEC("?tc")
+__log_level(2)
+__failure
+/* check that the first argument of bpf_wq_set_callback()
+ * is a correct bpf_wq pointer.
+ */
+__msg(": (85) call bpf_wq_set_callback_impl#") /* anchor message */
+__msg("off 1 doesn't point to 'struct bpf_wq' that is at 0")
+long test_wrong_wq_pointer_offset(void *ctx)
+{
+	int key = 0;
+	struct bpf_wq *wq;
+
+	wq = bpf_map_lookup_elem(&array, &key);
+	if (!wq)
+		return 1;
+
+	if (bpf_wq_init(wq, &array, 0))
+		return 2;
+
+	if (bpf_wq_set_callback((void *)wq + 1, wq_cb_sleepable, 0))
+		return 3;
+
+	return -22;
+}