1 files changed, 110 insertions, 8 deletions

diff --git a/tools/testing/selftests/bpf/xskxceiver.c b/tools/testing/selftests/bpf/xskxceiver.c
index 11f047b8af75..0ced4026ee44 100644
--- a/tools/testing/selftests/bpf/xskxceiver.c
+++ b/tools/testing/selftests/bpf/xskxceiver.c
@@ -524,6 +524,8 @@ static void __test_spec_init(struct test_spec *test, struct ifobject *ifobj_tx,
 	test->nb_sockets = 1;
 	test->fail = false;
 	test->set_ring = false;
+	test->adjust_tail = false;
+	test->adjust_tail_support = false;
 	test->mtu = MAX_ETH_PKT_SIZE;
 	test->xdp_prog_rx = ifobj_rx->xdp_progs->progs.xsk_def_prog;
 	test->xskmap_rx = ifobj_rx->xdp_progs->maps.xsk;
@@ -757,14 +759,15 @@ static struct pkt_stream *pkt_stream_clone(struct pkt_stream *pkt_stream)
 	return pkt_stream_generate(pkt_stream->nb_pkts, pkt_stream->pkts[0].len);
 }
 
-static void pkt_stream_replace(struct test_spec *test, u32 nb_pkts, u32 pkt_len)
+static void pkt_stream_replace_ifobject(struct ifobject *ifobj, u32 nb_pkts, u32 pkt_len)
 {
-	struct pkt_stream *pkt_stream;
+	ifobj->xsk->pkt_stream = pkt_stream_generate(nb_pkts, pkt_len);
+}
 
-	pkt_stream = pkt_stream_generate(nb_pkts, pkt_len);
-	test->ifobj_tx->xsk->pkt_stream = pkt_stream;
-	pkt_stream = pkt_stream_generate(nb_pkts, pkt_len);
-	test->ifobj_rx->xsk->pkt_stream = pkt_stream;
+static void pkt_stream_replace(struct test_spec *test, u32 nb_pkts, u32 pkt_len)
+{
+	pkt_stream_replace_ifobject(test->ifobj_tx, nb_pkts, pkt_len);
+	pkt_stream_replace_ifobject(test->ifobj_rx, nb_pkts, pkt_len);
 }
 
 static void __pkt_stream_replace_half(struct ifobject *ifobj, u32 pkt_len,
@@ -991,6 +994,31 @@ static bool is_metadata_correct(struct pkt *pkt, void *buffer, u64 addr)
 	return true;
 }
 
+static bool is_adjust_tail_supported(struct xsk_xdp_progs *skel_rx)
+{
+	struct bpf_map *data_map;
+	int adjust_value = 0;
+	int key = 0;
+	int ret;
+
+	data_map = bpf_object__find_map_by_name(skel_rx->obj, "xsk_xdp_.bss");
+	if (!data_map || !bpf_map__is_internal(data_map)) {
+		ksft_print_msg("Error: could not find bss section of XDP program\n");
+		exit_with_error(errno);
+	}
+
+	ret = bpf_map_lookup_elem(bpf_map__fd(data_map), &key, &adjust_value);
+	if (ret) {
+		ksft_print_msg("Error: bpf_map_lookup_elem failed with error %d\n", ret);
+		exit_with_error(errno);
+	}
+
+	/* Set the 'adjust_value' variable to -EOPNOTSUPP in the XDP program if the adjust_tail
+	 * helper is not supported. Skip the adjust_tail test case in this scenario.
+	 */
+	return adjust_value != -EOPNOTSUPP;
+}
+
 static bool is_frag_valid(struct xsk_umem_info *umem, u64 addr, u32 len, u32 expected_pkt_nb,
 			  u32 bytes_processed)
 {
@@ -1767,8 +1795,13 @@ static void *worker_testapp_validate_rx(void *arg)
 
 	if (!err && ifobject->validation_func)
 		err = ifobject->validation_func(ifobject);
-	if (err)
-		report_failure(test);
+
+	if (err) {
+		if (test->adjust_tail && !is_adjust_tail_supported(ifobject->xdp_progs))
+			test->adjust_tail_support = false;
+		else
+			report_failure(test);
+	}
 
 	pthread_exit(NULL);
 }
@@ -2515,6 +2548,71 @@ static int testapp_hw_sw_max_ring_size(struct test_spec *test)
 	return testapp_validate_traffic(test);
 }
 
+static int testapp_xdp_adjust_tail(struct test_spec *test, int adjust_value)
+{
+	struct xsk_xdp_progs *skel_rx = test->ifobj_rx->xdp_progs;
+	struct xsk_xdp_progs *skel_tx = test->ifobj_tx->xdp_progs;
+
+	test_spec_set_xdp_prog(test, skel_rx->progs.xsk_xdp_adjust_tail,
+			       skel_tx->progs.xsk_xdp_adjust_tail,
+			       skel_rx->maps.xsk, skel_tx->maps.xsk);
+
+	skel_rx->bss->adjust_value = adjust_value;
+
+	return testapp_validate_traffic(test);
+}
+
+static int testapp_adjust_tail(struct test_spec *test, u32 value, u32 pkt_len)
+{
+	int ret;
+
+	test->adjust_tail_support = true;
+	test->adjust_tail = true;
+	test->total_steps = 1;
+
+	pkt_stream_replace_ifobject(test->ifobj_tx, DEFAULT_BATCH_SIZE, pkt_len);
+	pkt_stream_replace_ifobject(test->ifobj_rx, DEFAULT_BATCH_SIZE, pkt_len + value);
+
+	ret = testapp_xdp_adjust_tail(test, value);
+	if (ret)
+		return ret;
+
+	if (!test->adjust_tail_support) {
+		ksft_test_result_skip("%s %sResize pkt with bpf_xdp_adjust_tail() not supported\n",
+				      mode_string(test), busy_poll_string(test));
+		return TEST_SKIP;
+	}
+
+	return 0;
+}
+
+static int testapp_adjust_tail_shrink(struct test_spec *test)
+{
+	/* Shrink by 4 bytes for testing purpose */
+	return testapp_adjust_tail(test, -4, MIN_PKT_SIZE * 2);
+}
+
+static int testapp_adjust_tail_shrink_mb(struct test_spec *test)
+{
+	test->mtu = MAX_ETH_JUMBO_SIZE;
+	/* Shrink by the frag size */
+	return testapp_adjust_tail(test, -XSK_UMEM__MAX_FRAME_SIZE, XSK_UMEM__LARGE_FRAME_SIZE * 2);
+}
+
+static int testapp_adjust_tail_grow(struct test_spec *test)
+{
+	/* Grow by 4 bytes for testing purpose */
+	return testapp_adjust_tail(test, 4, MIN_PKT_SIZE * 2);
+}
+
+static int testapp_adjust_tail_grow_mb(struct test_spec *test)
+{
+	test->mtu = MAX_ETH_JUMBO_SIZE;
+	/* Grow by (frag_size - last_frag_Size) - 1 to stay inside the last fragment */
+	return testapp_adjust_tail(test, (XSK_UMEM__MAX_FRAME_SIZE / 2) - 1,
+				   XSK_UMEM__LARGE_FRAME_SIZE * 2);
+}
+
 static void run_pkt_test(struct test_spec *test)
 {
 	int ret;
@@ -2621,6 +2719,10 @@ static const struct test_spec tests[] = {
 	{.name = "TOO_MANY_FRAGS", .test_func = testapp_too_many_frags},
 	{.name = "HW_SW_MIN_RING_SIZE", .test_func = testapp_hw_sw_min_ring_size},
 	{.name = "HW_SW_MAX_RING_SIZE", .test_func = testapp_hw_sw_max_ring_size},
+	{.name = "XDP_ADJUST_TAIL_SHRINK", .test_func = testapp_adjust_tail_shrink},
+	{.name = "XDP_ADJUST_TAIL_SHRINK_MULTI_BUFF", .test_func = testapp_adjust_tail_shrink_mb},
+	{.name = "XDP_ADJUST_TAIL_GROW", .test_func = testapp_adjust_tail_grow},
+	{.name = "XDP_ADJUST_TAIL_GROW_MULTI_BUFF", .test_func = testapp_adjust_tail_grow_mb},
 	};
 
 static void print_tests(void)