Commit fe8d561d authored by Benjamin Tissoires's avatar Benjamin Tissoires
Browse files

selftests/hid: add wq test for hid_bpf_input_report() 

Now that bpf_wq is available, we can write a test with it. Having
hid_bpf_input_report() waiting for the device means that we can
directly call it, and we get that event when the device is ready.

Link: https://patch.msgid.link/20240626-hid_hw_req_bpf-v2-10-cfd60fb6c79f@kernel.org


Acked-by: default avatarJiri Kosina <jkosina@suse.com>
Signed-off-by: default avatarBenjamin Tissoires <bentiss@kernel.org>
parent fa03f398

tools/testing/selftests/hid/hid_bpf.c

+38 −0
Original line number Diff line number Diff line
@@ -1130,6 +1130,44 @@ TEST_F(hid_bpf, test_hid_infinite_loop_output_report_call) 
				 err);

}



/*

 * Attach hid_multiply_event_wq to the given uhid device,

 * retrieve and open the matching hidraw node,

 * inject one event in the uhid device,

 * check that the program sees it and can add extra data

 */

TEST_F(hid_bpf, test_multiply_events_wq)

{

	const struct test_program progs[] = {

		{ .name = "hid_test_multiply_events_wq" },

	};

	__u8 buf[10] = {0};

	int err;



	LOAD_PROGRAMS(progs);



	/* inject one event */

	buf[0] = 1;

	buf[1] = 42;

	uhid_send_event(_metadata, self->uhid_fd, buf, 6);



	/* read the data from hidraw */

	memset(buf, 0, sizeof(buf));

	err = read(self->hidraw_fd, buf, sizeof(buf));

	ASSERT_EQ(err, 6) TH_LOG("read_hidraw");

	ASSERT_EQ(buf[0], 1);

	ASSERT_EQ(buf[1], 47);



	usleep(100000);



	/* read the data from hidraw */

	memset(buf, 0, sizeof(buf));

	err = read(self->hidraw_fd, buf, sizeof(buf));

	ASSERT_EQ(err, 9) TH_LOG("read_hidraw");

	ASSERT_EQ(buf[0], 2);

	ASSERT_EQ(buf[1], 3);

}



/*

 * Attach hid_insert{0,1,2} to the given uhid device,

 * retrieve and open the matching hidraw node,

tools/testing/selftests/hid/progs/hid.c

+79 −0
Original line number Diff line number Diff line
@@ -443,3 +443,82 @@ SEC(".struct_ops.link") 
struct hid_bpf_ops test_infinite_loop_output_report = {

	.hid_hw_output_report = (void *)hid_test_infinite_loop_output_report,

};



struct elem {

	struct bpf_wq work;

};



struct {

	__uint(type, BPF_MAP_TYPE_HASH);

	__uint(max_entries, 1);

	__type(key, int);

	__type(value, struct elem);

} hmap SEC(".maps");



static int wq_cb_sleepable(void *map, int *key, struct bpf_wq *work)

{

	__u8 buf[9] = {2, 3, 4, 5, 6, 7, 8, 9, 10};

	struct hid_bpf_ctx *hid_ctx;



	hid_ctx = hid_bpf_allocate_context(*key);

	if (!hid_ctx)

		return 0; /* EPERM check */



	hid_bpf_input_report(hid_ctx, HID_INPUT_REPORT, buf, sizeof(buf));



	hid_bpf_release_context(hid_ctx);



	return 0;

}



static int test_inject_input_report_callback(int *key)

{

	struct elem init = {}, *val;

	struct bpf_wq *wq;



	if (bpf_map_update_elem(&hmap, key, &init, 0))

		return -1;



	val = bpf_map_lookup_elem(&hmap, key);

	if (!val)

		return -2;



	wq = &val->work;

	if (bpf_wq_init(wq, &hmap, 0) != 0)

		return -3;



	if (bpf_wq_set_callback(wq, wq_cb_sleepable, 0))

		return -4;



	if (bpf_wq_start(wq, 0))

		return -5;



	return 0;

}



SEC("?struct_ops/hid_device_event")

int BPF_PROG(hid_test_multiply_events_wq, struct hid_bpf_ctx *hid_ctx, enum hid_report_type type)

{

	__u8 *data = hid_bpf_get_data(hid_ctx, 0 /* offset */, 9 /* size */);

	int hid = hid_ctx->hid->id;

	int ret;



	if (!data)

		return 0; /* EPERM check */



	if (data[0] != 1)

		return 0;



	ret = test_inject_input_report_callback(&hid);

	if (ret)

		return ret;



	data[1] += 5;



	return 0;

}



SEC(".struct_ops.link")

struct hid_bpf_ops test_multiply_events_wq = {

	.hid_device_event = (void *)hid_test_multiply_events_wq,

};

tools/testing/selftests/hid/progs/hid_bpf_helpers.h

+9 −0
Original line number Diff line number Diff line
@@ -90,4 +90,13 @@ extern int hid_bpf_input_report(struct hid_bpf_ctx *ctx, 
				__u8 *data,

				size_t buf__sz) __ksym;



/* bpf_wq implementation */

extern int bpf_wq_init(struct bpf_wq *wq, void *p__map, unsigned int flags) __weak __ksym;

extern int bpf_wq_start(struct bpf_wq *wq, unsigned int flags) __weak __ksym;

extern int bpf_wq_set_callback_impl(struct bpf_wq *wq,

		int (callback_fn)(void *map, int *key, struct bpf_wq *wq),

		unsigned int flags__k, void *aux__ign) __ksym;

#define bpf_wq_set_callback(timer, cb, flags) \

	bpf_wq_set_callback_impl(timer, cb, flags, NULL)



#endif /* __HID_BPF_HELPERS_H */